Here's the deal. Bike is running just great. Smooth as silk, little to no surging, MPG is in the mid 40's. Motor just purrs. Pipes are a beautiful shade of blue. Spot on throttle response. Best running Oilhead ( 1100 ) of the 4 I have owned. But......it hasn't has a valve adjustment or TB sync in 8,000 miles. Is this a case of " if it ain't broke, don't fix it ? " Or should I just have them both done and move on ?
Ya I agree. Check the valves. If the bike is smooth there's no real need to check the throttle body balance. It's likely the valves are ok too but if they tighten up it can cause expensive problems. And always replace the fuel filter on schedule or earlier. The lining in the steel tank fails on some bikes and the debris can clog the filter. That can cause a lean condition that is also potentially damaging.
So, you found the worry beads, eh? I'm going to change oil and check my valves soon, (about 10,000 since the last time)... There are two things that kill mechanical things; Dirt and stupidity. Keep the insides clean and beware of stupidity. You'll be fine.
I have found that my valves tend to tighten up a little if I spend a lot fotime up around redline. If you ride more conservatively, you're probably good for 10-12K miles.
After closing on 140,000 miles I've finally made enough thermal cycles that things are fairly stable. The last two checks were within spec, though I do tweak them a bit, well cause I'm there and I have the tools out and my hands are already dirty, might as well mess... I had this 1997 CBR 900RR, Honda I never needed to swap a shim on in over 100,000 miles including loads of trackdays, commuting and travel. I was at the track on that thing about once a month. That was one great motor.
It wasn't a worry beads question. It was more a if it's not broke question. I'm pretty anal about my bikes and probably take better care than I should, but none have ever failed me. Fresh dino every 2,500...new filter every other change. New syn in the trans and rear end every year. Don't run the bike hard, but do clip right along. But when the bike is running as good as this, well, why mess with it ?
For some the valves 'settle down' and won't need adjustment for quite some time. Checking them in and of itself doesn't change anything, but if you do make an adjustment you should also check the TB's due to their symbiotic relationship. JJ
Just check the valves, you will find it super easy and adjusting them is a breeze. I've found mine to get tighter after 10,000 miles. Better a tad loose than tighter, keep your eyes on those things. It easy to get them near as darn perfect.
OK stupid question of the day. There are several stats for valve clearance - so what do I set them to? The largest possible gap, or the smallest one? I checked mine after 17,000KM - and they are still at the minimum - so I loosen those puppies and increate greater than 15 and 30? Thanks Richard
Intakes 0.15mm and exhaust 0.30mm. This is the feeler size and does not have a tolerance. You should be able to push and pull the feeler with a slight drag if adjusted right.
Thanks Hog, that is what I set them for - but for some reason I thought thre was a tollerance on them ... my bad. I'll have to check my manual again So all is well in valve-land for me! Richard
If it's running good don't mess with it.. Maybe pull the covers and make sure you don't have a valve getting tight but that's it.. Surely don't mess with anything else.. :huh
For Oilheads. there WAS a tolerance. Then complaints of surging hit. Pragmitism tells us that .03MM too tight or loose will not cause the engine to self destruct. However, there will a some difference in air flow from one side to the other. With only one O2 sensor, then to keep the average mixture within reason,the Jug with the lower flow from the looser valves, will run rich and the other Jug will run lean. The lean one will have some lean misfire. Hence the surge. The more evenly balanced things are, valve clearance, carbon deposits, fuel injector flow rates, etc, the less the surge will occur. the Hex heads, with a O2 sensor for each Jug, are much less sensitive. Cars have had multiple O2 sensors since 97, to me it is inexcusable that it took BMW so long to do it with the bikes, since they knew they had issues. Just one of several completely avoidable MANAGEMENT decisions that tarnish the brand. This trend continues to this day. Ok, rant over. Rod
