New to me TZR250

[pdxjim]

During your carb cleaning, did you clean the little filters at the fuel inlet fittings?  The get gunked up pretty easy (especially if the tank was rusty), are easy to miss, not shown on parts diagram, and most don't even know they're there.

[m in sc]

i did not see them in there. I knew about them though... maybe i need to pull the tank take a look again just to satisfy my 'shit, did i check that?' doubts.

damn you jim. 

[m in sc]

fyi, pulled the tank after work and looked in there, nope, they were not in there. ran great on way home as well. 

[Striker1423]

nice!

[busa1300]

In case you need pistons in the future...

https://en.impex-jp.com/catalogs/moto/yamaha/tzr250/2ma-1987-white-ww-0036-england-5889/crankshaft-piston-232962.html

[m in sc]

thanks. you know i do now.. found low compression yesterday, 70 psi on one cyl, 100 on the right. top end time. DOH! 

[Kawtriplefreak]

Damn

[Evans Ward]

Sorry to read that Mark  but I know you'll do it right and will know this engine up close and personal.

[m in sc]

yup.

a bit more:
I should have checked compression when i got it, i knew better. However, it seemed to run well. My only experience with tzrs as a baseline was non stock ones, so i wasnt 100% sure what to expect.

i def did have some needle and seat issues. now that they are sorted (replaced) and the float level is set, i warmed it up in the garage and notices the RH cyl wasn't idling as strong as the left. temp gun on the headpipes showed 150-200 degrees less on the RH cyl vs left . i -knew- the carbs were clean yesterday as i had just rechecked them replacing the needle and seats. floats (round style) were set to 21mm.

midrange seemed ok. so when it was fully warm, temp gauge at 1/3~1/2, i decided to rev it out (10k) to see what it was doing. yup. RH cyl would then cut out at high rpm up high, or at least go in and out even under no load or with the speedometer out of the equation. a bit later i checked compression there it was.

well, at least now i have a small winter project.

[busa1300]

Would hate to go through all that work with new top end, and then have a old crank seal let some air in....

[m in sc]

oh... i hear you loud and clear.

[RDnuTZ]

Im so stoked i was able to finally get my hands on one of these. this came out of japan, recently, out of a collection.

Admittedly, I do not have a LOT of knowledge on these, but I'll figure it out.

for now, it need the tank cleaned and lined, it has a pretty wicked seam leak at the LH lower corner, not surprising.  Def needs some other things immediately:

fork seals
carbs cleaned
petcock rebuild or replaced.
coil remounted
brakes serviced (they are a bit sticky)
and probably a chain, tires aren't old surprisingly


I did get it fire up a bit, or at least fire off here and there but the carbs are, for sure, clogged up. so thats 1st order of business. I know it last ran in feb or march of this year.

My friends Adam and Dan were very gracious to pick this up for me, last minute, on their way from barber. (it did not come from there though).

This was one i always wanted after i rode one a few years ago, and im super pumped about it.







( you can see MSR's 73 350 in the background here)







and the most supportive wife in the world, was also pretty excited about it.

Nice find!  I've been sitting on a 1986 TZR250R (1KT) for 20 years now and not sure what to do with it at this point. It somehow made it's way from Japan to SF Bay area and got titled, changed owners (who tore it down for new top end) for a few years, relocated to San Diego where I bought it in I think 2003. Love the look and sound of these bikes!

[RdsOnly]

Yamaha Loves to Over complicate a retro race bike RZ500 comparison. THe stupid jet block and all the hoses...

  Fun bikes, love the look Glad you are sorting her out.

Yamaha LC250 was the best race bile for the street.

FYI you can make a TZ250 into a street bike.. Smaller carb to tame and other small adjustments.

Great collectors bike!!


JT

[m in sc]

actually, i didn't find it (the whole bike) complicated at all. .. on this, just a t fitting for the fuel lines, single feed to petock.  and this thing would destroy a regular LC250 stock to stock, built even more so.  I never had any desire to own a square or v 4 for the over complex nature of it though. 

anyway


cyls are off, getting a rebore to ,25 over, they looke dok but a refresh is due. rebuilding stock. will deal with the ignition and pipe upgrades later. head getting cut to bring it to a .8-.85mm squish.

cyl are at shop now, head at another shop, should have all those parts back next week. In the meantime, just cleaning stuff up from it sitting prior.

power valves needed a cleaning, also polished them a bit.

ring gap was almost 2x limit.  however, cyls and pistons looked really mechanically good.















all new pv seals and o rings as well, + new silicone hoses. ordered soem ;soft hose' specific clamps for them as well.

maybe running by the new year. 

[Kawtriplefreak]