magifesq Posted September 17, 2011 Report Share Posted September 17, 2011 If you ever rebuild your engine and have a pickup rotor like mine (1988 XR600 if you wanna check it out) make sure its properly installed, I put mine in upside down by mistake. I couldn't get spark...I reassembled it without the pickup coil installed / available @ the time or it would have been obvious. Anyways rotor reversed and now sparky is doing its job.Side note, I've been too lazy on this project all year lol, favorite excuse - the weather - cold has been too cold, heat too hot lol.Now I just need a new clutch cover gasket.Now for a technical question - how to figure compression ratio of the engine. Here's the story I was racing a deadline last fall (which I missed) to have the engine reassembled by end of september. I accidently broke the original piston rings when I was polishing the piston - buffing wheel grabbed it and slammed it against the wall, amazingly no damage to piston, rings were broken & shot. I ordered a replacement set of rings (that barely made it in time) that ended up not working at all - they didn't fit the piston, perhaps it was an aftermarket piston? Anyways I ended up speaking to an engine builder who pointed out the honda ring failures and explained to me the main thing is the rings condition, gap, and fitment - if they fit in the grooves properly, had like .0020 gap and didn't have excessive wear then they would be fine. I found a set of rings off of a TL1000S that I filed to spec and then they were a perfect fit. The Honda original bore piston compression ratio and wiseco cr was 9:1, the TL1000S cr was 11.3:1. So is the cr based mostly on piston and the cr unchanged, mostly on rings and now 11:1 +/- or in the middle around 10:1? Quote Link to comment Share on other sites More sharing options...
Gixxus Christ! Posted September 25, 2011 Report Share Posted September 25, 2011 Compression ratio has nothing to do with rings and everything to do with combustion chamber geometry. As long as the rings are file-fitted and you have propper gap tolerances all the way around they will perform the same regardless of compression ratio. Quote Link to comment Share on other sites More sharing options...
magifesq Posted October 3, 2011 Author Report Share Posted October 3, 2011 thanks, 9:1 it is then Quote Link to comment Share on other sites More sharing options...
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