Folks,
My son is riding his stock bore 2003 YZ85 in the 85-105cc 9-13 class. Lots of fast riders in that class--lots of KX/RM100s and loads of KTM105s. I have a nicked cylinder I'd like to overbore, but was wondering about reliability and maintenance issues with 92cc vs. 103cc kits. The cost of the work is roughly the same to bore to either size. Will the 103 require frequent piston or ring changes compared to taking it out to only 92? The stock bore engine Mr. Gorr built is pretty easy on pistons and rings. Are there other things I need to consider? I've got a big wheel kit for the bike as well.
Thanks much,
deadhead
My son is riding his stock bore 2003 YZ85 in the 85-105cc 9-13 class. Lots of fast riders in that class--lots of KX/RM100s and loads of KTM105s. I have a nicked cylinder I'd like to overbore, but was wondering about reliability and maintenance issues with 92cc vs. 103cc kits. The cost of the work is roughly the same to bore to either size. Will the 103 require frequent piston or ring changes compared to taking it out to only 92? The stock bore engine Mr. Gorr built is pretty easy on pistons and rings. Are there other things I need to consider? I've got a big wheel kit for the bike as well.
Thanks much,
deadhead
