92 blaster question

ttt

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Sep 10, 2017
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Hi , i am new to the forum and have a few questions .

I just bought a blaster , i believe its a 92 .
When i first bought it i didnt hear it run for ling because the silencer was barely connected . Had gas leaking from the carbs overflow , saw some oily build up by the exhaust flange because it was leaking im assuming .
When i got home i tightened up the exaust and put come high temp gasket sealer , took the carb off and cleaned it , inspected the reeds .

While doing so i looked through the intake and exhaust holes.
From the intake side it looks great very clean with no shinny spots or scoring .

On the exhaust side i saw alittle bit of shinny and it was only on the outer edges of the exhaust hole . Rings look good and i can acually hear and fill the compression .

I have not done and leak down test or compression test but it does have good compression .

Anyway fund's are limited and i know i should take it apart to make sure their not a bunch of piston play so mu question is .

Should i run it how it is ?

I will also include that i was told it has a big bore kit .
It has a toomey b1 exhaust
It has a Keihin pwk carb .

It fires up on the first kick cold with or without the choke 80 degrees in portland oregon

Im worried that their is piston slap and dont want to make things worse but i also dont have money to spend

Fire right up first kick , good throttle repsonse , i feel the compression .

What do you think ?
 
Ps : i did not check the jet size . I didnt check the jet size because i didnt know better but i will check soon . I havent been riding it
 
Hey! It's running! That is a good thing!
Now there are 2 big things to avoid: 1) blowing it up, 2) screwing it up
The best way to avoid these is to go slow at first, both in how you ride it and what work you do to it.

So, first of all, fix all the things that are obviously wrong like you did with the exhaust and carb, but do them one at a time. Fix the exhaust, then take it for a test ride to make sure all is well there. Then work on the carb and take it for a test ride to check your work. The reason for this "one at a time" rule is to simplify the troubleshooting process if it doesn't work when you get it back together.

These engines are prone to breaking piston skirts so having a look at the piston makes sense. It is no more than a 30 minute job if you have all the stuff you need. A new basegasket (usually cannot reuse), accurate vernier caliper to measure the piston, a leak tester, and some new plugs for jetting check. Seems like a lot of stuff but you really do need it to do a god job.

The goal is to take the exhaust and carb off, slide the cylinder off (head still on) and check the piston for cracks. If you see cracks, you have to order a new piston and cannot run the cracked one. You need to know the size of the piston to know what to order OR take the cylinder and piston to a bike shop/ machine shop to get it honed for the next larger size (recommended). No cracks? Slide the piston up in the bore and wiggle the skirts of the piston. If there is more than a little bit of play, you will still need another piston, but you can put it back together and run it gently while waiting. Very little play? You are good! Put it back together and do a leak test to check your work and your seals. Once it is running, do a plug chop (look it up) to check your jetting.

Seems like a lot of work, but once done right it should avoid the 2 big things.
 
Thank you , i havent done any recommendations yet.
I bought a 2nd blaster and im planning on buying piston kits for both of them i just dont have the money right now or time .




Iv changed the brakes on both of them and cleaned stuff up thats about it.

Until then im not riding them, well i might after i do a leakdown test so i can figure out the jetting . Im planning on riding in colder weather .
If it does good on a leakdown test and get it dialed with jetting should i run them with out a rebuild or is it not worth the risk?
Im mean they start pretty quick and idle?

Also should i ask any questions i mighy have in this thread or start a new one for every question ?
 

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If you have no sign (sound) of piston slap or bearing rattle, ride on!

Pulling the cylinder is not hard to do with these motors and a broken piston skirt is catastrophic, so I tend to pull the cylinder for a look if I am in doubt. Cracks in the piston skirt are the biggest hazard to look for, but also up and down play on the rod, piston clearance, and cylinder scratching (filter leaks).

Remember that with cold weather you need richer jetting.
full
 
Ok thanks , i want to pull it to inspect im just not sure what gaskets to order .

Will i not know until i take it apart ?
Im pretty sure they both have a big bore kit just noy 100% sure