'84 SR250 Garage build.

[kopcicle]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

http://www.dotheton.com/forum/index.php?topic=24283.msg259348#msg259348

might be some help btw use the viton O-ring and NOT the Buna- N .

~kop

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Thanks Kop, I will give that a read now while I wait for the chemicals to do their job.

As for the O-ring I didn't even know there were different types. I have a lot to learn yet. Thanks.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

All to often the novice will attempt to make up for other causes of flooding by bending the tab down onto the needle valve so far that no fuel will leak but also no fuel will flow . A general rule of thumb is if when upside down and the float adjustment tab is just resting on the needle valve adjust so that the float arm is parallel with the float bowl to carb body parting line . This only works if the floats have not been previously mangled .

The often over looked needle valve seat O-ring. When you can undo the needle valve seat retaining screw and plate and the seat falls out it's pretty obvious that the fuel isn't getting past your needle and seat . It's going around the seat . Replace the O-rings and be happy . Don't cut them on installation , use a bit of grease and they should press in firmly . Verify that this is your dimension and install away.

~kop

Very helpful Kop. So my thinking is as the O-ring on the seat split once a bit of carby cleaner hit it that there as a crack that was letting fuel past the float needle causing the dripping leak I had.

As for the screws at the top I had only just bought some socket head SS ones to replace the ones someone else destroyed. It is amazing what you can do with a dremel and an impact driver indeed.

 

[zap2504]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Several people have run into problems trying to use pod filters on Yamaha XJs (as well as other CV carbs). The proven fix has been to re-use the carb-to-airbox rubber connectors when installing the pod filters so a cleaner line of air hits all the air correction jets and CV vacuum port. If these are NLA, you can use rubber plumbing connection fittings in appropriate size to fit the outside of the carbs; found in most home centers.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Several people have run into problems trying to use pod filters on Yamaha XJs (as well as other CV carbs). The proven fix has been to re-use the carb-to-airbox rubber connectors when installing the pod filters so a cleaner line of air hits all the air correction jets and CV vacuum port. If these are NLA, you can use rubber plumbing connection fittings in appropriate size to fit the outside of the carbs; found in most home centers.

I had thought about that but I would rather have a bit of better filtration. I am thinking of grabbing a K&N for it as the only filters at the local bike stores were Uni and were a bit to costly for my liking. But on the other hand I would love to have a velocity stack on it to try and push as much power out of the 250 as possible.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

I spent the morning running around to all the local bike shops to get the same answer about the O-ring. Yamaha told me I would have to order the whole float seat if I wanted it at a grand price of $45, both the parts manager and I spent a good minute laughing and then he directed me to a bearing shop. The same shop I grabbed my wheel bearings from. When I went in I was able to get two sizes that would fit but neither in viton. After a bit of searching we found a viton ring that would fit and I took the other two as backup.

Once I was home I set head to rebuild the carby and I decided to take a few pictures on the way. I painted the top with some spare red paint I had just so in future people will know the carby has been looked at. After I put everything back in I had a look at the float height as Kop mentioned in his guide "Carburetors from the grave. www.dotheton.com/forum/index.php?topic=24283" and sure enough it was high. Someone had messed with this before me so I reset it and went on putting it back together.

After I had put the carby back on the bike it was still leaking petrol out of the air intake which had me wondering why. I started the bike and let it warm up then gave it a gut full and shut it off. I watched and waited but there was no leak so all is well.

I took her for a run around the block and the performance has improved greatly, I had her up to 70kph in second and she still had a bit to go. Now I just need to find an air filter that isn't going to mess with the CV carb.

Thanks for the help Kop.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Turns out I don't have the original intake pipe, just the air box. So I have been looking for a velocity stack to fit. Having next to no luck finding one in my budget I finally found an Aussie site which have a larger selection at a good price. They even have rolled edges which is exactly what I was after. http://www.jntperformance.com.au/index_c269035_2.html

I remember reading somewhere the other week about velocity stack lengths and an equation to work out what was best but can not remember where. I think it might have been linked on Texasstar's CB200 build.

I just went and checked how much room I have for the stack and it looks like 90mm is going to have to be the go unless I move the battery to somewhere else.

 

[eyhonda]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Sorry, late response on the cable vs hydraulic question (bottom of page 1):

The general feeling around the sportbike circles is that cable has a better feel than hydraulic. My cbr900rr had one but it was a bear in traffic. Smaller bikes won't have that issue though.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Thanks for the reply. I am thinking I will leave that for a while as it is not needed.

From all the reviews I have read people say it is smoother and feels better but there are a hell of a lot more people out there converting from hydro to cable.
I will give it a try some time in the future and decide for myself. If I don't like it I will stick it on my MiniCafe Z50A.


As for my grand idea of moving the battery it fell short by all of 10mm. I was planning to run longer bolts through where the rec/reg is mounted and make up a metal frame to hold the battery in.
I ordered a 125mm Velocity stack and moved the battery lower which looks a hell of a lot better than it did previously. I also tryed to tuck the leads up but will have to make a longer positive as there is just not enough room.

I will post up some pictures once I have all of it looking alright but for now the battery is mounted where it will stay until my welding skill increases greatly or I build a cafe seat.
The battery is mounted using the trusty old "Multi purpose adjustable mounting straps" AKA zip ties. See how it hold up :S

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

After a bit of soldering and cutting wires I have the battery mounted and the lead tucked away. The clips for the Reg/Rec annoy me and I will have to do something about them in the future but I am unsure if I will keep the Reg/Rec mounted where it is so I have left them for the moment.

Also while I was out taking a few pictures I pulled my XL250 to get a picture and have a run down the road on it. I plan on restoring it and using it as a two up bike for when the missus wants to come for a ride. I did a fair bit of riding on the XL when I was a teenager and it had a hard time since I jumped on it straight off a 1969 Z50A. She will get some loving in the years to come.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Just got a call from JNT Performance about the velocity stack. Stupid me had put in the wrong month for the expiry for my card. They have bloody awesome customer service and I will recommend them for anyone looking for stacks or performance piping! It is great that a company will call and chat rather than email.

http://www.jntperformance.com.au/

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

The stack turned up today and I am bloody happy with it. I have not had a chance to go for a ride since I put it on but it fits very snug on the BS34 and needed a few taps with a rubber mallet to seat it all the way down. Looks great as well. Props to JNT again for the customer service and awesome quality item.

I am going to have to make a inner guard now and have been thinking a few ways to do it. As I went through the options I think that clear perspex cut to fit will be the way to go.
Now I just need to find some. Off to the scrap bins I go.

 

[BoJordan]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

this is going to look delicious mate

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Thanks mate. Slowly making improvements. I wonder how the old girl will go pushing the Ton. I know next to know history about the engine and won't until I pull her apart for a rebuild in the future.

It is killing me not being able to ride on my own. Need to save up the cash for a full license haha. Too bloody expensive for my budget to allow. Soon enough.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Small update as I have had next to no progress on the bike. I fixed the side stand, made a temp inner guard and finished the rear end all in the space of three weeks. Ohh how I feel unproductive, I did change the stance a bit by raising the forks two inches in the triples. I know a lot of people frown on this but it feels to be more responsive which I am happy with. Anyway here is a picture of the new rear with the side stand fixed as well.

 

[Helak]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Liking how you've gone with this so far.

How have you found the 40t sprocket? Still got a 16t front sprocket?

And how has the Velocity stack treated you?

Look forward to seeing more from you soon.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Hey mate. Sorry for the late reply. The bike has been at a stand still of late. I still have not been able to give it enough testing to tell but then I did not have any before to compare it to. It pulls quite well for a 250 and have had it to 110kph without making it scream. I will be able to give it a better test in a month or so and I can sus out what needs changing and what is good. So far the 40T rear and 16T front works quite well.

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

I road the bike to work last night and learnt a lot of things. I will list them just so I remember what I need to fix and so people can see the joys of riding a classic.

1. My headlight SUCKS!
2. All the gauge lights are out
3. I didn't fix the clutch slipping when I was adjusting the cable
4. My bike is not faster than a small car
5. Bar end mirrors suck at night
and finally
6. The charging system does not work well enough to power a headlight and let me start the bike the next morning.


So I am thinking that I may need new clutch springs for the slipping issue as it seemed to be happening well after the clutch had disengaged. I am also thinking I should buy a new LED headlight and a new REC/REG to see if that sorts out the charging issue (having a tiny battery does not help either). I also have a feeling that I may have had some water intake this morning leaving me thinking that the velocity stack might gain a bit of dew during the night. (She was parked outside at the girlfriends place.)

 

[Brodie]

Re: '84 SR250 Garage build. Solo Tracker now, Cafe later.

Alright so here is a quick update. No pictures yet sorry. I have bought a new headlight that draws 3w on low beam and 9w on high. This seems to have fixed the problem I was having with the light running the battery down. I also found that my steering became quite heavy on the way home from work one wet afternoon. Seemed to be falling in to turns when I went through them as well. Wanting to get home and out of the rain I took it a bit slower and once I was home had a look. Seems all the air decided to evacuate at once and I was left with a flat. Being that it was an old and hard tyre that needed to be replace because it was hard it help up alright.
Today I decided it was time to grab a new front tyre and thought it might be easier if I had it fitted and balanced instead of me wrestling with a hard tyre on an old rim (been there, done that PITA)
When I went to pick the front wheel up the mech informed me that he didn't balance it because he had a hard time seating the new tyre and that I "would not be going fast enough for a balance to matter on my bike". After I informed him of what speeds I have done on it he informed me not to because I would "do a big end bearing". He also told me next time not to bring a rim in on a saturday as it was a "tuesday job". Needless to say I was not impressed with the attitude but was sympathetic knowing that it would have been a PITA. All in all not sure if I will go back there since every time I have dealt with them over 4 years they have been rude or unwilling to help. Was not planning on taking it there today but they were one of two places that had the right size tyre.

 

[Brodie]

Alright so I have finally decided to get off my ass and update this thread. So I have been working on a few things but really have just been fixing problems. I have been having an issue with the clutch and after trying to convert it to a hydraulic style I have given up and gone back to cable. I ordered some new clutch springs today which should hopefully fix the issue once and for all. I have been able to adjust the cable so that it is not slipping to much any more but it seems to go away once the bike is warmed up.

As for the charging issue I was having it has been fixed by the new headlight. As an added advantage I CAN SEE IN FRONT OF ME NOW! The new LED headlight compared to the original is night and day (pun intended) So that seems to be all good. The battery has been staying full charged and I have not had to push start the bike since.

Now I need to sort out the jetting. I need at least a size up on each which I will go and get tomorrow on my day off. I also seem to have an erratic idle problem until the bike is warmed up. I am thinking this is because of having a CV carb with a velocity stack stuck on it. Thursday I will be heading over to a friend house to work on his bike. An unmolested SR250 that is in need of a top end rebuild.

I have a few plans for this bike but I know I will need to force myself to buy a part until I will get motivated to start with it. It is going to be expensive but worth it. Just need a 83mm piston to start with then a good machine shop. Once I sort out these bills (never ending I tell you) I might be able to get somewhere.

Anyway here are a few pictures to see progress. The first is how she sits as of three weeks ago. Not much has changed apart from the headlight and front tyre.
Second is the new headlight, third is with the park light on and last is everything off but new front tyre.