I bought a new Yamaha V-Max back in 86 and put 95000 miles on it. I checked the valves once at 50,000 and once at 90,000, and each time the clearances were well within tolerances. Isn't checking the GS's valves every 4000 miles a bit much---especially if you are an "easy" rider like I am.



                   Rick.

Quote from: ojstinson on March 23, 2009, 06:00:52 PM
I bought a new Yamaha V-Max back in 86 and put 95000 miles on it. I checked the valves once at 50,000 and once at 90,000, and each time the clearances were well within tolerances. Isn't checking the GS's valves every 4000 miles a bit much---especially if you are an "easy" rider like I am.



                   Rick.

Welcome to the world of air cooled bikes. The valve seats do wear. GSJack will chime in eventually, but as I recall, he never had to change intake shims, but did have to change exhaust shims on occasion... He's a good source because he's actually put all of the miles on his GS. My GS is high mileage (nearly 88,000 miles) but I've only owned it for the last year. For what its worth, I have changed some shims in my bike already, and the previous owner did it at least a couple of times in the 5 years he owned it... I'd imagine the V-Max doesn't go through valve shims as much because it operates at a much lower temperature. The GS will have a head temp of 350-400 degrees Fahrenheit even with only easy riding on a warm day...

Two words: air-cooled

VMax is water cooled, right?

I'm not an engineer (nor do I play one on TV), but my understanding is that because of the wider temperature range in an air-cooled engine the tolerances have to be looser to allow for metal expansion/contraction.

A water-cooled engine can have tighter tolerances because the operating temperature range is relatively narrow.

Looser tolerances mean things get out of adjustment more quickly.

That makes sense, thanks for the info.

Everything said above is true, but 4,000 miles is a ridiculously low adjustment interval for GS 500 valves, even though it's air cooled.  Let me tell you what the dealer told me about my last bike, a 1982 Yamaha Seca 650, which I bought new from him.  The Seca was technologically identical to the GS, it just had 4 cylinders.

He said to bring it in for adjustment after the break-in period, then again at about 12,000 miles, then it'll probably be good till 50,000 miles if you change your oil on time and not sit in traffic for long periods.  Keep in mind this is NY, not NM, but that's the advice I got 25 years ago.

He also said some folks bring their bucket and shim air-cooled bikes in every couple years for a valve adjustment, but then get mad when they pay all that money only to find out their clearances were still in spec.

Ya know Bill, I think what you said, and what you were told is a whole lot closer to the way things really are than those "service requirements" state. I think what they put in the manual in respect to service intervals is a combination of covering their asses during warranty, and making money doing the service work--- which is pretty pricey in most cases.
Thanks for the input.



        Rick.

By 50 K I had atleast 10 swaps of it and cos I run it very tight it was lesser than it could have been, and my bike always needed thicker and thicker shims.
Cool.
Buddha.

I checked the valves at about 600 miles on my 97 GS and then decided to do it at 8k mile intervals after that.  Changed my first shim at almost 40k miles on the cyl 2 exhaust valve.  Changed the other exhaust shim at about 49k miles and and it was then good until I parked the bike at 80k miles as were the 2 intake shims that were never changed.  But that cyl 2 exhaust valve required repeated shim changes and was down to the minimum 215 shim at 80k miles.  All shim changes were to smaller shims as the exhaust valves receded into the seats.

Why?  Notice on my valve clearance log that the cyl 2 exhaust valve clearance ran at a minimum .001" for many thousands of miles before the first shim change while the other had a minimum of .002" clearance, more cooling time on the seat I believe.

My 02 GS valve check record was interupted by a broken exhaust valve caused by a tight bucket at 21k miles.  I repaired it and now at about 67.6k miles it still runs as good as new.  When I noticed the cyl 1 exhaust valve required a couple shim changes in a row and it was also running on the tight side of clearances as the one on the other bike I decided to set exhaust valves looser, as much as .005" clearance when changing shims.  It worked, no further shim changes in another 20k miles.  The valve recession was stopped I believe.  Will be making another valve shim check in the next month or two and see how it's going.

http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg

The above post was jumping all over as I typed it so I posted it and continue here.  I had an air cooled 82 CB750K that I put 80k miles on and it wasn't eating exhaust valves like my 97 GS was so I went back and checked the specs.  Valve clearances were .002-.005" and redline was 9500 rpm.  Sounded good to me, a stock GS like both of mine have been doesn't need to go over 9500 rpm.  Power peak is about 8500 rpm.  So I now set my GS500 valve clearances at .002-.005" and my redline at 9500 rpm.  Works for me and if you set your valves at .005" and then throw a shim redlining it don't blame me. 

Thanks for the info. Jack, I get the feeling that you run all your bikes pretty hard and fast, I like to ride faster than I should, but I don't think any of my bikes have seen redline---usually not even close. Does moderate to semi-fast riding usually extend the life of proper lifter clearances?

How often did you change the oil on your high mileage bikes?