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Main Area => General GS500 Discussion => Topic started by: bluespy on June 03, 2008, 09:16:12 AM

Title: valve check: should rear wheel spin smoothly?
Post by: bluespy on June 03, 2008, 09:16:12 AM
I checked my valves after watching Kerry's video.  (Thanks again Kerry.)  To turn the engine, I mimicked the procedure of putting the bike on the center stand, changing to 6th gear, and then spinning the rear wheel by hand.  I had removed the spark plugs to reduce compression.  I noticed that as I spun the wheel it was sometimes easy, but sometimes quite difficult, to turn.  My guess at the time was that it was difficult to spin when the exhaust valves were being opened.

Is it normal that the wheel would be very difficult to turn part of the time?


BTW, all my valves were in spec.  This was a welcome change from the ninja 250 that I had before the GS.  The ninja had half of the miles (4k vs. 8k) but seven of eight valves were tight.  When I did the ninja, I turned the engine using a breaker bar.
Title: Re: valve check: should rear wheel spin smoothly?
Post by: Ry_Guy on June 03, 2008, 09:56:02 AM
It's normal, at least for my GS. I have the same thing before and after a valve adjustment. I think it's because one of the camlobes is depressing a valve during part of the rotation, which requires a little more force.
Title: Re: valve check: should rear wheel spin smoothly?
Post by: ohgood on June 03, 2008, 10:04:10 AM
check your chain for bad/tight links. it may be shot. ya, there is -some- reistance, but it shouldn't be hard to turn the wheel.
Title: Re: valve check: should rear wheel spin smoothly?
Post by: The Buddha on June 03, 2008, 11:04:40 AM
With the bike in gear without plugs too, you're moving a ton of stuff, transmission, clutch, crankshaft, counterbalancer and pistons and cams ... a lot of load, you are now making the 25 lb torque it can make. Yes its tight in some spots and loose else where ... depending on whether weights are getting pushed up or down.
Cool.
Buddha.
Title: Re: valve check: should rear wheel spin smoothly?
Post by: simon79 on June 03, 2008, 11:22:47 AM
^^^^
I'd say Buddha is right.
I did a couple valve check/adjustments -6th gear on and plugs off-, and the rear wheel would offer some resistance sometimes.
Nothing weird. :thumb:
Title: Re: valve check: should rear wheel spin smoothly?
Post by: bluespy on June 03, 2008, 01:20:41 PM
Thanks for all the replies.  I did look at the chain (lubed it actually since today I crossed 600 miles since I last lubed it), and confirmed that the wheel spins freely in neutral.

So, given the bulk of the comments, I'll assume that the resistance when in gear is normal in this case.