Yamaha Discussions about Yamaha ATVs.

high compression 727

Thread Tools
 
Search this Thread
 
Old May 17, 2004 | 12:46 AM
  #1  
sandRappy's Avatar
Thread Starter
|
Trailblazer
Joined: Apr 2003
Posts: 68
Likes: 0
Default high compression 727

Ooops, sorry about about the blank post. Anyway what I was wondering is if anyone with a 727 or 730 that has high compression pistons have had any problems with them?

I finally got mine together and some time on it. Then I have been messing around with the carb setup. So the other day I finally get the carb tuned into where I am not lean and I can ride it hard. After a short run seeing how it runs I bring it back to the shop and it has oil all over the engine. Long story short, one stud that holds the jug to the cases pulled out the threads, while the other rear stud was loose.

I have no idea why this happened. I am only running a 12:1 JE, but apperantly that is a little to much compression for it to hold. I know those studs were torqued correctly. One stud was completely stirped out will the other rear stud was very loose compared to the front two studs.

Also since this is the first time I have riden the bike hard I noticed it was vibrating really really bad. Is this normal with a 730? I had the crank reblanced with the new piston and rod so I thought it would run smoother then it did stock, but it feels like there is no counter balance in the thing. Even though the jug was held down by only three bolts I don't think is should vibrate like this.

Is anyone running a 730 with out heili coils (sp?) I was because I didn't think I would need them.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
pgamboa
Chinese Quads
18
Dec 24, 2023 11:52 AM
2quiker
Yamaha
11
Mar 22, 2022 08:36 PM
bvolks
Kawasaki
8
Sep 13, 2015 12:57 PM
Steeldon
Polaris Ask an Expert! In fond memory of Old Polaris Tech.
4
Sep 9, 2015 09:38 AM
Steeldon
Utility ATVs
0
Sep 5, 2015 09:38 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 



All times are GMT -5. The time now is 05:00 AM.