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Discussion Starter #1
Hello all. Just got my wifes bike back together with a Wiseco 68mm piston and a sleeve bore.

It runs very well but....

It has inconsistent idle. It will sometimes idle down perfectly. Other times when it idles down it idles high as if the choke was on. After of few seconds of high idle it then will kick down and either idle normally or barely idle b/c it kicked down super low.

Is there a direction I should head to try to work through this issue?

Jetting with the new piston?

Adjustment I am missing somewhere?

Not sure...

Thank you,
Rob
Kent, WA
 

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Hanging and inconsistent idle is the trademark sign of a vacuum leak. The easy way to confirm this is to wave an unlit torch around the carb boot and intake. If the engine speeds up, you know it's sucking the propane in. You can use this to find the actual point of the leak with a fair degree of accuracy.

Ensure the carb boot was not damaged in the process and everything is clamped up firmly.

I've found the stock vs Wiseco pistons do not have a substantial effect on jetting. If it ran good with the stock piston, it should be fine with the Wiseco. The only difference is the higher compression of the Wiseco means the engine uses more of it's inertia on the compression stroke, so you generally need to turn the idle up slightly. 1/2 turn on the idle stop and it's fine.
 

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Hello all. Just got my wifes bike back together with a Wiseco 68mm piston and a sleeve bore. It runs very well but....
Why did you bore the cylinder ? Dirt ingestion, lean seizure or just worn out piston?
 

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Discussion Starter #9
The bike is a 1994. My wife fell in love with the color scheme and literally chose a TW because of the color. She has since fell in love with the bike for what it is. I own a motorcycle rental business so she rides allot of different bike but would ride the TW exclusively if she could.

The carb wasn't apart for the engine work...just was off for about two months.

The cylinder was bored b/c: long story as short as possible:
1) The bike threw the valve adjustment bolt
2) That mushroomed the valve
3) Replaced valve and lapped the seats (i work at a high school and the auto shop at school helped me out)
4) Reassembled and ran.......BUUUUUUT.....I messed up the adjustment on the cam chain tensioner and got it way too tight with shredded the plastic.
5) That caused oil starvation which seized the cam on the sleeve....replaced the cam and did the cam bearing upgrade instead of the sleeve.
6) Ran after the cam replacement but with a knock. Knock was the piston sleeve not being happy with the cylinder.
7) Sent the cylinder and pistion to LA Sleeve in CA and they bored it and cut the rings.
8) Reassembled....started right up.

It's super super close. We have done the break in procedure. She's ridden is about 100 miles. We took it out on the dirt trails today and it really worked well. RIGHT when we think its absolutely perfect it won't idle down. Then if we turn the idle down the next time we go to run it it won't run b/c the idle is too low.

We'll get there....its super close and were happy.
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