Valve adjust specs after 25,000+ miles on the 82

Terry · Post by **Terry** » Fri May 08, 2009 9:19 pm

Only four were out of spec, two, too tight and two, too loose (barely). Here are the numbers for anyone worried about the timeliness of adjusting them per the book.

.14/.10 .02/.09 .13/.08 .10/.11 .02/.09 .09/.08

.13/.14 .11/.10 .08/.09 .08/.09 .10/.09 .10/.13

Not bad for 92,000+ miles eh? But I'm still wondering if I should ride the 79 on tour this summer, seeing as how its the 30th anniversary and all...

EMS · Post by **EMS** » Sat May 09, 2009 9:28 am

Under "normal" circumstances the clearance gets tighter over time as the valve head and seat get cosy with each other. There is little I can think of that would make a valve clearance larger other than wear on shims

alimey4u2 · Post by **alimey4u2** » Sat May 09, 2009 2:20 pm

EMS wrote: There is little I can think of that would make a valve clearance larger other than wear on shims

Heavy carbonization on the valve seats but that is a thing of the past. Cam wear but that doesn't seem to be a problem with CBX's. Cam journal wear, doubtful ?? Most likely it's settled down (debris under the shim) from an earlier adjustment that was on the edge of tolerance....

EMS · Post by **EMS** » Sat May 09, 2009 3:13 pm

Cam wear - I was thinking about that. But wouldn't that be unlikely to affect valve clearance?? Cam wear usually occurs on the lobes, were there is metal-to-metal contact. The valve clearance, however, is measured on the ground of the camshaft where there is no contact and should be no wear...????

alimey4u2 · Post by **alimey4u2** » Sat May 09, 2009 3:34 pm

EMS wrote:Cam wear - I was thinking about that. But wouldn't that be unlikely to affect valve clearance?? Cam wear usually occurs on the lobes, were there is metal-to-metal contact. The valve clearance, however, is measured on the ground of the camshaft where there is no contact and should be no wear...????

You are indeed right Mike, thank you for the correction....

EMS · Post by **EMS** » Sat May 09, 2009 5:15 pm

alimey4u2 wrote:
EMS wrote: You are indeed right Mike, thank you for the correction....

It was not intended to be one, Larry. I wasn't sure myself

Cam wear would sure cause a noise indicating a large valve clearance...

alimey4u2 · Post by **alimey4u2** » Sat May 09, 2009 5:59 pm

EMS wrote:It was not intended to be one, Larry

I know that Mike, it's good that we can openly question each others thoughts, makes for a better forum....

Terry · Post by **Terry** » Sat May 09, 2009 9:54 pm

Come on, I thought you were all going to yell at me for waiting so long...

cbxtacy · Post by **cbxtacy** » Sat May 09, 2009 11:51 pm

Don't look at me, Terry. I do mine every 60,000 miles or 10 years, whichever comes first, whether they need them or not.