1981 Yamaha SR250 Cafe Racer

[lunar_c]

Right .. exams are over and I had a day off .. so I spent most of it working on the bike.. it felt great!

So when I modified the frame at the beginning of the build I left a couple of brackets on that were for the seat latch by accident.. they cluttered up the lines of the frame at the rear and I wanted to keep the fibreglass tail nice and slim, so they had to go..

I then repainted the rear section of the frame, can't tell now. Much better!

While I was at it I re-drilled the holes for my rear indicators so I could mount those before I start fibreglassing up the seat next week.

Can't wait to finish the rear up with the duck tail.. will do the number plate mount etc tomorrow too.

I repainted my new switchgear and have started test-fitting all of that up .. going to buy new levers and grips tomorrow!

Finally .. I have been struggling with space in the original design I made to house all of my electrics under the seat / tail .. the box was too small, so I used my CAD (Cardboard Aided Design) skills today to design the new tray that will run the full length of the seat subframe and give me much more space in which to put my fuse box, cdi, reg, etc etc.

I also re-made the rear inner guard from 2mm aluminium sheet so I can polish it.. and I'll be finishing the dash board from the same material soon.. More pics tomorrow!

Cheers,
Ben

 

[JRK5892]

looking sick man! when you say duck tail... do you mean a dove tail fender? I am not sure what a duck tail is? please do not take that as being a smart ass i honestly was just wondering if that is the name for modding the rear of the frame like you have?

 

[Disco]

I really like how you are using the original tank wit this Project... Im following along closely getting ideas..

 

[DBLshotcafe]

good to see the exams are over and your back into it! great job on the build so far, have given me alot of ideas for my big arse money pit.

 

[lunar_c]

Cheers guys!

Today I picked up some new grips and levers ..

This is the simple "rego version" of the dashboard.. just waiting for my speedo to come before I cut the hole for the gauge. The three bezels are for indicators, neutral and hi beam light. They're clear leds that light up coloured.. pretty sweet.

Back to work tomorrow but more work on the bike will be done over the weekend ..

 

[lunar_c]

Finished repainting the switchgear and perches and got them all fitted up. I made new labels for them with a label maker and trimmed them to fit in the little recesses on the casings. I like the cockpit view! Just waiting on the speedo now to finish it off.

I also got the cables run for the clutch and throttle .. but because of the lower height of the ace bars, I'll need to shorten them or have some made .. currently they're a bit daggy.

More to come tomorrow, cheers.

 

[HotelBushranger]

I like the droopy cables, reminds me of a Norton Dominator or something

 

[mattb]

I also got the cables run for the clutch and throttle .. but because of the lower height of the ace bars, I'll need to shorten them or have some made .. currently they're a bit daggy.

Adrian at Vanem http://www.vanem.com.au/ supplies shorter cables for cafe racer SR500s; I don't know if they are the same or not to the 250 - you could always email him some pics or post yours to him to find out (or he might have dealt with this question before)...

Matt

 

[gunnabuild1]

Good to see this is still moving along, one of the sweetest builds going.
Simple and very very clean.
Love the details.

 

[lunar_c]

The old box I used for the electronics wasn't big enough so I bent up a box to the right dimensions (using all available room under the seat area) out of 2mm aluminium plate and test fitted it this evening. Everything fits comfortably this time! I'll mount it tomorrow.

Going to do a lot more work on the bike tomorrow and wednesday as I have them off work!

 

[Yani]

This build looks awesome!!!
So much so I just picked up a SR to do something similar.
Where did you get the handlebars from?

 

[10417549]

This build looks awesome!!!
So much so I just picked up a SR to do something similar.
Where did you get the handlebars from?

Yep, same here dude. Just bought one. I'm following your build like gospel Ben!

I've been shopping around a bit (8 hours a day) for a tank. SR250's aren't that popular... However there's plenty of SR400/500 parts about. Do you know where I can learn how to put a SR400 tank on to the 250 properly?

 

[lunar_c]

update

Did a bit more work today. Got the electronics tray mounted then put the rear wheel on and checked for clearance. I had to modify the battery tray clear the rear wheel but everything worked out nicely enough.

Here's what lives inside .. missing the fuse box in this pic though :

I put the front end together quickly to again check for clearance and so on and try two different front guard designs I had mocked up.. with the wheels (unfinished) back on I am really loving the profile of the bike, though I would love an 18" rear wheel to finish it off.

With the bobbed SR250 front fender I made :

The whole bike .. it'll be nice once I detail those wheels and put some new tyres on!

More pics/progress tomorrow..

 

[midlifecafe]

I'm gonna use every idea you've had. Shameless stealing but it's such a good build. I'm at the cleaning the motor stage hoping to be going by summer.

 

[lunar_c]

Some good progress today!

Big thanks to my friend JB for letting me use his sandblasting cabinet for the day.

I cleaned up my wheels/hubs by blasting with garnet.. I will mask them off and paint the spokes and hubs with an epoxy enamel soon, leaving the rims as the chrome is good.

I decided to sandblast the carb body to a raw aluminium finish leaving the polished float bowl and gloss black diaphragm cover to see how I like that. It breaks up the black on the bike which is good.

I hooked up the crankcase breather nipple on the crankcases to a small filter/breather which to prevent smoking, I stuffed with steel wool.

Here's the polished brake plate back on the front wheel .. I'm going to paint the brake arms black though.

 

[jiggas]

I'm seeing good things Lunar_C ! you're nearly there.
Your bike on PSB is what lead me to here and is what lead me to my little project.
It must be good to see something cool come out of not too much expense and a pretty ugly start point?

 

[lunar_c]

Today was a good day tinkering with the bike!

I checked the cush drive rubbers inside the hub on the rear wheel. The bearings are doing okay too.

Maybe it's the cable (feels free enough but maybe the inner conduit is worn, I'll replace it later for a shorter one anyway), but I felt that the throttle return was a little lazy on the carb, so I made a little bracket and added an additional spring to aid throttle return. Looks good to me and works nicely.

Speaking of cables, the original plating on all the cable end fittings was pretty rusty, so I wire brushed them and painted the ends with gloss black epoxy enamel. Neat.

What I am most excited about though, is that I started shaping the seat/duck tail today.

What I did was buy a couple of those thin blue camping mat's you find at camping stores, cut it into sections and glue them together .. this was a very cheap way to have a nice big block of high density foam (around $10) any dimensions I needed.

This was then roughly shaped using a kitchen knife, then shaped with a flap wheel sanding disc on a grinder. The trick when shaping the foam is not to put any weight on the work with the grinder (ie you must support the grinder's weight) or you'll go further than you intended to. These pics are the result of about 15mins work. Please wear a dust mask and eye protection or the inside of your lungs will be blue.

I'm still working out the proportions of the duck tail .. I put up a tarp and took some pictures so I could work it all out in my head. I think it's a little high at the moment. Be kind, I know it needs more shaping..

This then gets covered with plaster of paris (easier to sand and mix up in big quantities than auto filler and much cheaper) and sanded smooth, then you have a male plug with which to lay and impregnate the fibreglass chop matting over. The smoother you get the plug, the less filler you will need later on the work itself.

This is then released from the fibreglass .. then you can reinforce the bottom of it with more chop mat if needed, then cover it in a thin coat of auto filler .. sand smooth, prime and paint.

I will paint the tail the same colour as the tank and may put a panel for a number on it. I have a rough tail lamp to set into it also.

Regards,
Ben

 

[Tombad]

Hey Ben
been following your project from the start (love your work) i also have a sr250 81 model which was being thrown out and was in really bad shape with surface rust on just about everything and it is missing the CDI and Coil. Also after making comparisons to mine and yours i realized the front end on my bike was of a completely different bike and the axle was also bent making it RS.

So after finding out the front end was R.S. I went and bought the whole front end off a CB250RS to take advantage of the Disc brakes. After spacing the forks out 8mm it fit into the old SR250 triple clamp and makes the bike look completely different while maintaining the Spoke look. Just thought i should share this with you In case you were thinking about getting a bigger wheel up front or going for disc brakes. And anyone else who might be looking for disc brakes for their SR250.

Also If anyone who visits this forum has a spare CDI and Coil (with lead) off an 81 model that they are keen to get rid of in exchange for Cash Please PM me as i am having some trouble finding parts for this bike that are not from a dealer paying their premium prices.

Your doing an excellent job and i cant wait to see how your seat turns out as i opted for the easy way out and just shortened my rear guard and flattened off the original seat and re wrapped it in vinyl to give it the flattened look.

 

[boingk]

The smoother you get the plug, the less filler you will need later on the work itself

.

Man, did I ever learn that the hard way on my tailpiece! Hahaha....

Anywho, looking very nice at the moment. Seriously like the shape of the tail, just wondering if you've looked at it a bit with the bike sitting level. I know mine didn't look right to me until I shaped a bit of it with the bike not sitting on its centre stand. Apart from that its all good, you'll have an easier time with the tail than I did.

Cheers - boingk

 

[lunar_c]

Right .. here's a proper update!

I ordered a POSH 87mm speedo through Vanem and mounted it up tonight on the alloy bracket I designed a while back. Underneath are three led bezels for indicators/high beam/neutral.

Here is a view from the side. I styled the whole set up after a BSA gold star clubman.

And from the front..

And here's me alongside the bike. As you can see, at 6'5" I'm a little big for the bike so I will probably sell it later on, but geez it's looking good!

This is a shot of the real wheel when I was painting it.. so much masking, ugh!

First up, I had to make a relief in the headlight bucket to clear the speedometer cable. With the new gauge being at a different angle to the old unit, it fouled the headlight bucket.

Secondly, after adding clubman bars the steering lock needs to be reduced to stop the handlebars fouling on the tank. I devised a method of doing this by drilling and tapping the original steering lock tabs on the lower triple tree to accept an M6 x 12mm socket headed bolt .. allowing the steering stops to be adjusted to suit.

Finally, here's the tail section "hump" with another coat of filler on it .. it's almost ready for sanding and shaping.

Cheers,
Ben