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Blood Sweat Tears and Grease => Projects => Enduro / Dirt / Scramblers => Topic started by: Sonreir on Mar 26, 2019, 17:55:36

Title: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Mar 26, 2019, 17:55:36
Grabbed this bad boy for $350 over the weekend. Missing just about everything (including paperwork) and someone tried to convert it to MX at some point. The engine sputtered on starter fluid, so hopefully everything is OK in that department.

Plans are to bring it back to a streetable state, so I'm on the lookout for a tank and seat. The left engine case is also missing, so I'll have to track down one of those. 12V DC conversion is in its future.

I can't wait to start throwing cash at this money pit. :P
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: cb360j on Mar 26, 2019, 18:20:45
That is dope. Is titling on a bike with lost title hard where you are?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Mar 26, 2019, 18:39:34
I'm going to try the Vermont trick and see how it goes. If that doesn't pan out, I have a friend who's specially registered with the state and can get me a title for anything.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: advCo on Mar 26, 2019, 19:21:32
I'm in.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: WhyNot on Mar 26, 2019, 20:24:14
I'm in too.

Would like to have something like this to fool with.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Pete12 on Mar 27, 2019, 08:33:52
I've got a bunch of DT stuff at home, mainly later models, but I'll have a look when I get back in a couple of weeks.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Mar 27, 2019, 12:33:52
I took things apart a little bit last night.

Tank is definitely plastic and looks to never have been used. There's still a little yellow overspray on the inside, which I assume the gasoline would have made short work of.

Wheels are almost definitely not stock. I don't think this bike would have come with shouldered aluminum? There are also there weird bolts poking out at regular intervals. Purpose?

Finally, I didn't realize that the DTs had a compression release? Unless this is something else.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Turnturtle on Mar 27, 2019, 13:45:14
Those bolts are clamps (rim locks) to keep the tire from slipping on the rim. They have to be loosened before you can remove the tire.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: pidjones on Mar 27, 2019, 14:38:44
The tank has had gas in it, or the cap came from another tank.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on Mar 27, 2019, 16:44:02
Rims are DID and look the same as were used on road racers and motocross bikes.  That suggests that the rims or wheels may have come from a MX version of that bike or something similar.  Also possible that a PO re-spoked the wheels with rims from a different bike. What diameter are they?  The front sticker appears to say 1.60 - ....  I can't read the diameter.  The front hub looks like a DT style rather than MX250 style. Rear could be either, so probably re-spoked.

They are like the rims fitted to a TD3 which had a 1.60 -18 but the spoke angle would be wildly different on that bike. We picked up a NOS 1.60 -18 at a swap meet a few years ago and it ended up on the front of a CB160 road racer. They are generally slightly lighter than the H section flanged (Akront style) rims we all used to love.

Turnturtle is correct.  That's a rim lock to prevent the tire moving on the rim when it runs with low air pressure for more grip.

BTW, what ignition is hiding under the end cover?  Has it been fitted with an internal rotor Hitachi CDI or just a weight loss external rotor street design?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Mar 27, 2019, 18:09:53
Looks like the ignition is probably stock? I need to dig in further.

The ignition coil is one of those small orange ones you see on scooters and the like.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: pacomotorstuff on Mar 28, 2019, 08:04:08
Hey Matt,
The decompressor aka "deke" looks to be aftermarket - maybe a Yamaha accessory.  The DT's came with the head already tapped (and with an aluminum "plug" in it) for either a second spark plug or a deke.  A deke really helps slow down a two stroke - especially when those skinny ass old drum brakes get wet LOL.  Had one on my 250 dirt tracker and used it instead of the brake most of the time.
Unless you're trying to do a "Pebble Beach" resto, I'd keep the tank you have - probably period-correct.  Match it with a Preston Petty enduro headlight / number plate and some Petty fenders (they're making them again if you can't find NOS ones) and you'll look like an enduro guy from 1975.
The rims are a nice upgrade - the DT's still had steel rims as far as I remember (but I HATE rim locks LOL).
Had a couple of DT2's of similar vintage, got rid of them and am low key looking for a CT1 or CT2 (the 175cc enduro), as I found the 250 a bit big for me (I'm slow, old and not very tall LOL#2).
Get rid of the rear shocks - they look way too long to me - put on an old school Circle Industries fork brace and you'll be good to go.
Will be watching this build.
Pat

Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on Mar 28, 2019, 10:45:29
Good news about the ignition as long as the PO left the lighting coil/s inside. And if not, it should be easy to find a similar unit that will do the job.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: JustinLonghorn on Mar 28, 2019, 12:39:32
I’m on board.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Mar 28, 2019, 12:58:56
Hey Matt,
The decompressor aka "deke" looks to be aftermarket - maybe a Yamaha accessory.  The DT's came with the head already tapped (and with an aluminum "plug" in it) for either a second spark plug or a deke.  A deke really helps slow down a two stroke - especially when those skinny ass old drum brakes get wet LOL.  Had one on my 250 dirt tracker and used it instead of the brake most of the time.
Unless you're trying to do a "Pebble Beach" resto, I'd keep the tank you have - probably period-correct.  Match it with a Preston Petty enduro headlight / number plate and some Petty fenders (they're making them again if you can't find NOS ones) and you'll look like an enduro guy from 1975.
The rims are a nice upgrade - the DT's still had steel rims as far as I remember (but I HATE rim locks LOL).
Had a couple of DT2's of similar vintage, got rid of them and am low key looking for a CT1 or CT2 (the 175cc enduro), as I found the 250 a bit big for me (I'm slow, old and not very tall LOL#2).
Get rid of the rear shocks - they look way too long to me - put on an old school Circle Industries fork brace and you'll be good to go.
Will be watching this build.
Pat



Thanks, Pat!

I now have a Petty rear fender and three number plates on the way.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Rider52 on Mar 28, 2019, 16:07:05
"I now have a Petty rear fender and three number plates on the way."

Perfect! I was hoping you would keep the tank and add Petty fenders. This is going to be a fun bike!
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Mar 29, 2019, 13:58:10
Very much leaning toward something like this for the tank...
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Mar 29, 2019, 23:27:03
I own a dt250 DT2. do yourself a favor and throw out the rim lock. I used tiny square cut from a tin can and plumbers epoxy. makes for a smooth ride over 50 instead of an angular momentum tsunami. when you have this part in your hand you will see what I'm talking about. I run a 17t JT front sprocket. put shinko 244's. they definitly don't help on grooved highways or bridges.

tortured myself with the 6 to 12 conversion. did not unground the stator. I floated ground. yes it worked full wave. at idle it was 8v with the stock headlight. you need to run an LED headlight if you want to run batteryless.

if your carb is jetted like mine it comes with a 60 pilot. pollution was not a thing, today it pisses people off. 35 will still run like stink.

cool project, kept mine stock except for lane splitter bars because I live in NYC. mine does not have a decompression valve. vermont went fine with mine.
 
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: irk miller on Mar 30, 2019, 10:23:51
Takes a lot of weights, but you can balance a rim with rim locks. On bikes I run on the street, but do real single track, I run them. If you’re dropping air pressure for off-road, they’re important. That said, if you’re running mostly street and nothing more than fire roads off-road, then get rid of them. It won’t hurt to keep that hole open, but I put a strip of duct tape, folded sticky side in, over the spokes.


Sent from my iPhone using DO THE TON
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Mar 30, 2019, 16:22:31
Takes a lot of weights, but you can balance a rim with rim locks. On bikes I run on the street, but do real single track, I run them. If you’re dropping air pressure for off-road, they’re important. That said, if you’re running mostly street and nothing more than fire roads off-road, then get rid of them. It won’t hurt to keep that hole open, but I put a strip of duct tape, folded sticky side in, over the spokes.


Sent from my iPhone using DO THE TON

its easy to do a good repair, go with the physics. EK=1/2m x v squared. you always want to loose weight and this crap is heavy. instead of adding lots of dead weight to compensate put the thing into the round file, do a quality repair of the rim and never look back. the 250 is rated at 20 hp so its not much of a stump puller. some contact cement a piece of leather over the hole, but I'm a jb weld and tin snips kind of guy.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: irk miller on Mar 30, 2019, 18:48:29
its easy to do a good repair, go with the physics. EK=1/2m x v squared. you always want to loose weight and this crap is heavy. instead of adding lots of dead weight to compensate put the thing into the round file, do a quality repair of the rim and never look back. the 250 is rated at 20 hp so its not much of a stump puller. some contact cement a piece of leather over the hole, but I'm a jb weld and tin snips kind of guy.
What are you talking about?  Your math doesn't mean shit when you don't know what you're talking about.  A rim lock isn't for repairs or whatever you think it is.  It's for when you run really low pressure in your tires for better grip riding off-road.  Sometimes, it doesn't take much to throw a tire when there's less that 15psi in them.  20hp is more than the 18hp my XR200 has, but I run rim locks because I actually take it on trails.  I also run rims with an open hole all the time . You don't really need anything in there.  The duck tape is for covering the backside of the spoke nipples.  It's stiffer than the the rubber band they usually run, so if you worry about it, it keeps any amount of tube from bulging into the hole.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Mar 30, 2019, 22:05:53

told you upfront I would get into trouble on this site. physics trumps all. all this stupid math matters. I always strip out dead weight and do modern repairs. angular momentum rises exponentially with speed and at some time you want to ride on the highway.

I own a DT2. I did the 6-12 conversion by making a negative and positive regulator floating the ground and running full wave. rode over 1,000 miles many on the highway on a mint green plate. I lane split in the city and ride to the beach in the summer. no regrets, always turns heads. how many people can say they did that. I definitly know some shit. I know I dont want to ride on the highway with a hole in a rim when I run pressures closer to 40psi.

It's a 2T. that means you scream in the power band 20hp at 6k rpm, at 3500 its more like 14. with a 17t front sprocket it rides like the worlds biggest moped. I'll never float ground agin and I'm with justin longhorn, I be watching this build
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: irk miller on Mar 30, 2019, 22:36:43
told you upfront I would get into trouble on this site. physics trumps all. all this stupid math matters. I always strip out dead weight and do modern repairs. angular momentum rises exponentially with speed and at some time you want to ride on the highway.

I own a DT2. I did the 6-12 conversion by making a negative and positive regulator floating the ground and running full wave. rode over 1,000 miles many on the highway on a mint green plate. I lane split in the city and ride to the beach in the summer. no regrets, always turns heads. how many people can say they did that. I definitly know some shit. I know I dont want to ride on the highway with a hole in a rim when I run pressures closer to 40psi.

It's a 2T. that means you scream in the power band 20hp at 6k rpm, at 3500 its more like 14. with a 17t front sprocket it rides like the worlds biggest moped. I'll never float ground agin and I'm with justin longhorn, I be watching this build
Can you read? How many times do I have to say for trail riding? You’re not in trouble, you do not read to comprehend things. The motion pro bead lock weighs a whopping 72 grams. We can all do ourselves a favor and disregard dirt bike advice from a guy that splits lanes in NYC.


Sent from my iPhone using DO THE TON
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Mar 31, 2019, 17:25:38
agreed the motion pro rim lock weighs 72 grams. the DT2 was designed in 1968 with very few changes over the years. the stock antique rim lock is too heavy to balance properly. also I get about 2 flat tires a year. the streets here are awful. getting rid of it makes changing tires much easier. that paint scheme has meaning to us 2 strokers. speed.

keep the rim locks and the #60 pilot and ride on the dirt half inflated. 1/4 mile blue rooster guaranteed ticket on the street though. they look for that kind of stuff.
 
I'm not telling anyone to do anything. but I will tell what I've done and how it works. how many people can say they they built got a transferrable registration and own a DT2. I know shit because I'v been there already. I know what to do the next time because of the mistakes I've made the first time I built it.

If it were me I'd keep the stock ignition. it has a dedicated stator. all LED's and half wave on the 6 to 12v on the lighting side with a scoot regulator. get rid of the antique rim lock and balance the tires. 17t front sprocket. #35 pilot and new needle valve. I use the bootleg mikuni pz type with the neoprene tip. this way you keep the seat. easy way to modernize the carb with neoprene and the spring on the float. lane splitter bars. integrated signals. legal on a bike thats illegal to ride on the street. I wave to the man when I ride and he waves back. there is nothing wrong with riding with the tire pressure recommended on the tire and lanesplitting is not a crime.

I'll be watching this one because it's personal.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Apr 01, 2019, 09:26:13
btw the stock rims are stamped and chromed steel. they suck because of the weight. po did you a favor there. the stock tank is steel and a thing of beauty. mine is black white and orange. my seat is different. has a hinge and locks. I run 150 on the main jet. if the carb is still the stock vm28. my frame has all the same tabs but yours is missing some stuff. like the oil tank, battery box, muffler heat shield.


I bought the DT2 after watching jay lenno's show. it was one of the first enduro's. what it lacks in performance it makes up for with style.

I'll be the first one to say don't take dirt bike advise from me. 2 stroke porn for everyones viewing pleasure.

(https://i.postimg.cc/4yKhyW3T/DSC02190-2.jpg)
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 08, 2019, 11:56:11
Used Petty rear fender arrived and the brackets line up perfectly with the frame mounts. So that's nice.

Recommendations for cleaning it up? Will plastic polish bring it back to a new look?

Looks like some damage to the frame cross brace though?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: irk miller on Apr 08, 2019, 12:17:19
Wetsand from 150 to 1500 or 2k grit, then buff.  Just like paint.  Here's a good video that describes the process pretty well...

https://www.youtube.com/watch?v=Fwk_fNEeH6Q
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: canyoncarver on Apr 08, 2019, 12:36:56
Dude...I'm in.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 08, 2019, 12:48:04
I restored all the plastics on my KLR last year, it's a bit of a ball ache truth be told.  But absolutely doable - mine were really faded.  Basically you have to sand back all the sun damage and then sand the scratches left by that using increasingly finer grade paper all the way up to 2000 grit.  The plastic is pretty unforgiving though - make sure you really get all the scratches out from the coarser paper with the next grade up, or you never will.  Here's another vid on how to do it (this is the vid I followed) -

. https://www.youtube.com/watch?v=yWPwCXLSIdA

It takes a while man, get beer.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 08, 2019, 12:51:30
Or, there's a much quicker method - using a blowtorch (or a heatgun).  It melts the sun-bleached surface back to the original colour, but I think the results are a bit iffy.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Rider52 on Apr 08, 2019, 13:38:32
I have a couple of small Suzuki's, a JR50 and an ALT50, both had weathered plastics. I had them stored at a friend's shop and he restored the plastics by scraping them with a razor blade. I've seen some You Tube videos and some other forum remarks on doing this. 
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: irk miller on Apr 08, 2019, 14:19:24
Did anyone watch the Youtube vid I posted?  LOL.

Lots of ways to do this, but I've done a lot of plastics the way Jim and described up front and the results work every time.  Scraping with a blade is doing the same thing (removing oxidized plastic), but a blade doesn't exactly make as clean of a surface.  The only other real way to do it is to chemically convert it with something like acetone, but the results won't exactly be good.  The blow torch works too but all it is doing is melting the oxidized plastic into the not oxidized plastic.  It's not really changing it back.  The ABS has zero resistance to UV, so it literally breaks down in the sun.  You have to remove the broken down layer to get into the good layer, which will eventually break down too.  Some times a little labor produces the best results.  You wouldn't want your paint shop cutting corners on your paint job, would you?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 08, 2019, 15:03:26
Here's a fairing I restored using the sanding method -

(https://i.imgur.com/bS1LGsP.jpg)

There was a huge KLR sticker on it, peeling that off showed just how oxidized the rest of the panel was (underneath the sticker of course it looked mint).  I won't lie, it takes quite a few hours and a lot of beer.  The vids'll tell you what grade paper to start with, and I finished by polishing with Maguires polishing compound.  Make sure not to buff too long on one spot or you'll melt the plastic and that will absolutely suck balls.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Apr 08, 2019, 22:58:35
Did anyone watch the Youtube vid I posted?  LOL.



Why watch a video when there's gloss black paint. I know my limitations as a mechanic. anything I think lools crappy gets painted oil based enamal. you saw the pic, it works. my dt2 rear fender is kawasaki green because it came off a kdx but you can't tell because its black. I won't lie, it takes a couple of minutes and a lot of beer. 
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 08, 2019, 23:02:18

Why watch a video when there's gloss black paint. I know my limitations as a mechanic. anything I think lools crappy gets painted oil based enamal. you saw the pic, it works. my dt2 rear fender is kawasaki green because it came off a kdx but you can't tell because its black. I won't lie, it takes a couple of minutes and a lot of beer.

^ or that  ;D
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Popeye SXM on Apr 09, 2019, 00:03:02
Quote
my dt2 rear fender is kawasaki green because it came off a kdx but you can't tell because its black.
Until it gets scratched!
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: irk miller on Apr 09, 2019, 08:28:39

Why watch a video when there's gloss black paint. I know my limitations as a mechanic. anything I think lools crappy gets painted oil based enamal. you saw the pic, it works. my dt2 rear fender is kawasaki green because it came off a kdx but you can't tell because its black. I won't lie, it takes a couple of minutes and a lot of beer.
And here I thought we were talking about restoring plastics, not copping out on a mid-Atlantic custom. 
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: pidjones on Apr 09, 2019, 09:21:44
The video was helpful for me. I'll need to use a bit more than 320 on my GL1000 meter surround. The decal in front of them had been scraped off roughly by a PO (they do make plastic blades - I bought some at West Marine), and the area on top has some wrinkles I'd like to remove. I think it had a textured finish, but don't mind making it smooth. Next winter.... (It's showing well now, though). I used the heat gun method on the inner fender piece - really nice at smoothing out the scrapes that develop on the inside. Have to be VERY careful not to over-heat and distort, though. Acetone will usually cloud ABS, so you would still have to sand or buff that layer off. The good thing about ABS is that it can be glued easily with ABS plumbing cement and cleaner. I built a whole new under-cowl piece for a CB750F out of wrecked GL1800 ABS pieces.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 10, 2019, 10:55:14
More tear down finished last night. I also got the frame de-tabbed since I'll be running the aftermarket seat and no original side covers.

I found an interesting rear spacer when the wheel came off  and the brake cable holders on the the front and the rear wheels are both broken. The rear wheel is also dented (which I hadn't noticed before).

And for some reason, some one got a bit crazy with an angle grinder up front.

Up next is engine disassembly.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: advCo on Apr 10, 2019, 11:00:47
I have a NOS 3.00x18 aluminum rim that would probably work there.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 10, 2019, 11:04:02
Thanks, man. I'll check the width and let you know. I'm hoping to go a bit thinner than what's on there right now. The brake stay was actually bolted to the outside of the hub (rather than have the hub slot through the fork in the stay) because the rear tire was too wide.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: killerx on Apr 10, 2019, 11:28:58
 You can get the rim back into shape with a dead blow hammer.
Unless there is something else wrong with it.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 10, 2019, 12:10:09
You can get the rim back into shape with a dead blow hammer.
Unless there is something else wrong with it.

Thanks. I wasn't sure if it was an easy repair or not. I still might investigate other options because I want to go narrower on the rear tire and I'm not yet sure what will fit.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: killerx on Apr 10, 2019, 13:17:54
If the tire /tube holds air, over inflate it some, then start pounding.
I've always started right in the middle since that is where the impact that caused the bend in the first place.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 15, 2019, 13:29:00
The previous owner went crazy with an angle grinder, so I figured one good turn deserves another. Flipped the wire feed welder into low voltage mode and started filling in the gouges. Definitely not perfect, but it's an improvement. I might go over it one more time before I hit it with the flappy-sanding thingy.

Engine tear down started and I broke the clutch basket, so time to hit eBay again. I got the usual number of stuck screws and will need to drill a couple of them out.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 16, 2019, 11:19:44
A little bit of welding and a lot of grinding later, I have an electronics tray. I still think I want to work out some sort of cross brace near the shock mounts, though...
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 17, 2019, 10:57:54
Started on the rear fender clean up last night. Went over the fender with an orbital sander and 320 grit. I'll start the hand sanding tonight.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 17, 2019, 11:25:38
Looking like a good start - one thing I found out is that any scratches/sun bleaching that you don't get out with the coarser grit you never will. 
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 17, 2019, 11:26:35
For sure. I'm going back to start at 220 grit when I do the hand sanding, I just didn't want to go too course with the power sander.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 17, 2019, 11:39:41
Right on - get some beers within arm's reach.  Good chance you'll need em   :o
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Maritime on Apr 17, 2019, 11:47:18
That fender will require 12+ beers to complete I am sure ;D
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 17, 2019, 12:10:15
That fender will require 12+ beers to complete I am sure ;D

per grit  :o
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 19, 2019, 15:03:16
Finished the wet sanding through to 1000 grit and then hit it with some plastic polish. Not perfect, but suitable for something that will be covered with dirt and mud. :P
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 23, 2019, 12:31:48
I started mocking up the front number plate and what will pass for my headlights.

I'm using two of our 20W flood lights: http://www.sparckmoto.com/Products/Detail/84

One will act as high beam and the other as low beam. Turn signals are still in progress.

I also stripped off the last of the foam and rusted metal from the seat pan. A little fiberglass work will be necessary before sending it off to my upholstery guy.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 23, 2019, 12:49:41
Hey man nice job on that fender.  How many beers did it take?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: advCo on Apr 23, 2019, 12:50:31
Looking good so far. I like the headlight/number plate combo.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 23, 2019, 12:52:22
Hey man nice job on that fender.  How many beers did it take?

Sadly, none. My wife picked up some hard kombucha (can you tell we're from Oregon?) and I had a few of those, instead. Ended up taking about four hours in all.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Jimbonaut on Apr 23, 2019, 13:02:34
Beer, hard kombucha, frontal lobe lobotomy...whatever it takes
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Turnturtle on Apr 23, 2019, 18:30:06
(https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTg6kSlTwj5FIkmOjUjl6H_rqq19plRpWJD7j1qZOwn8bSipcXV)
Just sayin'.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 24, 2019, 11:18:14
I was thinking I'd put eye lashes on the lights. lol
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 24, 2019, 12:08:31
Started work on the stator for the DT2. Removed the coils for the lighting, charging, and ignition systems. We're going to a full 12V DC system, so all three coils will be rewound in series to create a single phase alternator.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on Apr 24, 2019, 13:30:39
So the fine wire coil is the ignition charge coil and the other pair are for charging, or are all three charge coils?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 24, 2019, 13:43:45
The small gauge wire is for the ignition coil and the other two are for lighting and charging, respectively.

One and a half of the thicker gauge coils are wound to provide power to the headlight, tail light, and brake light systems. Turn signals and horn are run from the battery, which gets fed (through a half-wave rectifier) from the other half winding.

My goal is to wind all three in series and rectify the entire stator so that we'll be running on 12V DC. We'll need a new ignition coil as the old AC one will no longer be suitable. All lights will be converted to 12V LED.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on Apr 24, 2019, 13:46:36
Sounds like an interesting plan. Is there enough magnetic flux to generate a solid 12v?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 24, 2019, 13:48:41
That's what I'm going to find out. The plan is to start with 16 gauge wire, but I can bump it up to 18 gauge (smaller wire means more windings and more windings means higher voltage) if I don't like the numbers we're putting down.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on Apr 24, 2019, 14:00:08
And if that doesn't work, there's always PowerDynao (Vape) or HPI but the cost is a little higher.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 25, 2019, 13:45:21
Hmmm... you ever kinda want to do something, but you're not really sure if you should?

I found this stator I had laying around in the shop and it's wound for three phase. The magnet overlap on the rotor looks pretty close to ideal and the stator is almost a perfect fit. I think the stator may have been from a GSXR?

I would have to completely rework the ignition system, but I think the charging system would be top notch.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Maritime on Apr 25, 2019, 13:46:35
Wow. Looks made to fit
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Apr 25, 2019, 13:54:58
Wow. Looks made to fit


I know, right? The mounting holes are in the same locations on the stator bracket as well. I'd just need to turn down the mounts for the points and old coils and this stator would bolt right up.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: canyoncarver on May 01, 2019, 11:48:12
I know, right? The mounting holes are in the same locations on the stator bracket as well. I'd just need to turn down the mounts for the points and old coils and this stator would bolt right up.

Why not adapt a Dyna instead of points after all that work?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on May 01, 2019, 15:46:35
Toying with the idea... I need to find some room inside the cases.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on May 02, 2019, 09:54:35
WOuld the rotating magnets in the flywheel not mess with the dyna pickups?  I know that people fit DYNA's to RD350s with an internal rotor and they seem to work OK.  I haven't tried one on an external flywheel.  Cheap enough to try.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on May 02, 2019, 11:06:23
WOuld the rotating magnets in the flywheel not mess with the dyna pickups?  I know that people fit DYNA's to RD350s with an internal rotor and they seem to work OK.  I haven't tried one on an external flywheel.  Cheap enough to try.

That was my thinking, which is why space becomes an issue. Not sure where else to put it aside the rotor. Maybe something on the primary gear?
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on May 02, 2019, 19:08:00
That's always a possibility but you need a pickup that can withstand hot(ish) oil.

Is there a later model DT250 that came with CDI that would bolt on?  I did have a Hitachi single pickup system at one time (basically 1/2 a TZ system), but that had no lights.  Not cheap but how about an HPI small rotor set up or maybe a powerdynamo/Vape large external flywheel system. 

https://hvccycle.net/yamaha-dt-rt-dt250-dt360-dt400-cdi-ignition-12v-180w-7238799dc/

https://www.hpi.be/item.php?item=210K059

Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on May 08, 2019, 22:40:09
Got two of these bad boys wound. We'll see how it works out...
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on May 30, 2019, 13:19:42
Got the chamber back from Pacific Pipe Repair. They pulled the dents and laid on some fresh black coating. Not 100% sure what the coating is, but I'm assuming it'll hold up to the heat.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: SF on May 30, 2019, 20:43:42
Looks new


Sent from my iPhone using Tapatalk
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Sonreir on Jun 04, 2019, 10:50:20
The decals for the front and side number plates came in. Looks pretty good, I think.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: JustinLonghorn on Jun 04, 2019, 10:58:27
I can dig it.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: Rider52 on Jun 04, 2019, 16:31:56
Looks great!
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: crazypj on Jun 04, 2019, 16:55:37
Never much of a fan of the 250 as it's a bit porky (lot of gravity in there)  a 360 or 400 drops right in and with minor port work plus exhaust you hav ea 120mph dirt bike  8) Those wheels maybe  direct from the MX bike, none flanged alloy was stock on them. They can be re-shaped pretty easy, I've done worse and made them look like-new. Just loosen off all the spokes in the bad area and anneal with a propane blowlamp. Put some hand soap on the inside rim flange, when it turns black your good to go with a dead-blow mallet or 4lb  'lump' hammer and wood blocks
That's always a possibility but you need a pickup that can withstand hot(ish) oil.

Is there a later model DT250 that came with CDI that would bolt on?  I did have a Hitachi single pickup system at one time (basically 1/2 a TZ system), but that had no lights.  Not cheap but how about an HPI small rotor set up or maybe a powerdynamo/Vape large external flywheel system. 

https://hvccycle.net/yamaha-dt-rt-dt250-dt360-dt400-cdi-ignition-12v-180w-7238799dc/ (https://hvccycle.net/yamaha-dt-rt-dt250-dt360-dt400-cdi-ignition-12v-180w-7238799dc/)

https://www.hpi.be/item.php?item=210K059 (https://www.hpi.be/item.php?item=210K059)
     The later MX (monoshock) had electronic ignition. Don't remember exact spec but advance curve was totally different on the DT400M<X and stock it was bit of a slug. Fit 250 ignition plus Franconi or similar pipe and it will out accelerate a Kawasaki KX400 then run away at top end, even with stock carb (I think 34mm?)
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Jun 15, 2019, 23:17:13
Started work on the stator for the DT2. Removed the coils for the lighting, charging, and ignition systems. We're going to a full 12V DC system, so all three coils will be rewound in series to create a single phase alternator.

did that stator. kept the ac ignition because its stupid simple and I can run without a battery. ungrounded the headlight stator and ran 2 phase full wave for the lights and horn. did not need to use the tail stator with the taps. removed it.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: teazer on Jun 18, 2019, 19:24:48
Polaris - at least on some of their older sleds - ran AC to the lights and CDI ignition.  They had a simple two wire regulator too - probably just a zener diode to dump excess volts to melt snow.
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: crazypj on Jun 19, 2019, 00:17:01
WOuld the rotating magnets in the flywheel not mess with the dyna pickups?  I know that people fit DYNA's to RD350s with an internal rotor and they seem to work OK.  I haven't tried one on an external flywheel.  Cheap enough to try.
Later DT250/400MX had electronic ignition
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Jun 20, 2019, 10:31:41
Later DT250/400MX had electronic ignition

as well as early 360's
Title: Re: Yamaha DT2 Build - Smoke if you got 'em...
Post by: bracketmaker on Jun 21, 2019, 10:22:52
Polaris - at least on some of their older sleds - ran AC to the lights and CDI ignition.  They had a simple two wire regulator too - probably just a zener diode to dump excess volts to melt snow.

thats a common offroad setup. not just polaris, many dirtbikes and quads run ac lighting. the 2 wire ac regulator is a voltage clipper. I don't run this way because led's don't run ac. mark on the 2 stroke forum does. my kdx ran this way stock. rectified to half wave dc, regulated with a shunt regulator. (as opposed to floating ground to make street legal).

the rewound stator pic shows where this build is going. I just ungrounded the lighting coil and never looked back.