I just checked my valve clearances on the fixer i just picked up, and one of the exhaust valves had a 261 shim. i bumped it up to 270 and there's still about a .09mm clearance. obvious issues aside, how large a shim should be needed before i consider changing out the valve assembly (valve seats, springs, seals)? im on a budget and dreading the need to put more money into this bike. -__-
Shim replacements should be smaller over time, not larger shims. The valve clearances should tighten over time. I don't know what would cause them to loosen, they should get smaller.
I believe the largest is around 2.80? Smallest is around 2.20?
well whoever did the clearance last must have done something wrong.. because i had a 260 in there.. and needed a 270+ i sure hope i didnt get lemon'ed. motorcycles dont make good lemonade.
any other ideas of what could be going on without tearing down the whole motor? it seemed to run ok, other than hanging idle (probly from exhaust valve not opening enough) but i havent been able to check on the carbs yet.
i almost feel cheated by the person who sold me the bike.
I would ride for a few weeks/months (depending on how frequently you ride) and check them again. Say, 500 or 1000 miles. It could just be that they didn't calculate the right shim sizes.
Shims come in .05mm increments from 2.15-3.10mm. I'd leave an exhaust valve shim in there that gives a .09mm clearance. I've never had an exhaust valve clearance increase in over 150k GS500 miles. They just get tighter for me but that can be slowed down by giving them a bit more clearance. Intake valve clearances don't change much at all.
http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg
i bought the bike and theoretically the carbs had just been rebuilt. with that said, maybe i'll try and trust them and throw the carbs back on now that i've re-shimmed the valves. maybe that'll fix the hanging idle.. if not than i'll continue with my original plans to take apart and rebuild the carbs myself.
there are plenty of "how-to's" for rejetting the bike.. but how about the stock settings? if i use stock pilot (37.5) and main (122.5) jets, how many turns out should the pilot screw be?
Stock from the factory, depending on locality, is lean at around 2 or 2.5 turns.
Quote from: romulux on April 23, 2010, 04:43:39 PM
Stock from the factory, depending on locality, is lean at around 2 or 2.5 turns.
Thanks! i'll keep that in mind