my XJ600 Valve specs

Hi Peeps,

As you all have been most gracious and told me to"check your valve gaps".
I did the very deed today.

I had an exhaust at .09mm :?

A thought occurred to me; I know there is a permitted variance in gaps, but would it be better to have all the gaps the same. IE IN at .15mm and and the EX at .20mm?

just thought it might make the engine better!

thoughts please ?

 

They don't need to be the same, just in spec. You don't really get a benefit if the intake and exhaust are the same as their neighbors.

Suggestion, put your bike in your .sig so people can identify you with the bike. It will help in answering more specific questions. Good job at attacking the clearances!

 

cool thanks

 

Truthfully, it would be marvelous if all of the gaps could be equal as you suggested. You'd have one happy motor.

But shims come in .05mm increments.

The only way to have them all the same would be to custom machine odd-sized shims; except shims are case-hardened so it's truly not practical. At least not in a mass-produced bike.

Or, grind the tips of the valves slightly. I believe this is the preferred method for race-engine builders on motors of similar configuration. Again, not practical for mass application.

Remember, if frogs had wings...

 

done the deed now, got an official yamaha valve tool for £10 and it was easy.

just ordered a 260 shim for ex as the other two, I could just swap shims over from the 3 valves that were out of spec.

 

all sorted, carbs stripped and cleaned. did the clunk test set the floats.

tightened up the oil gear behind the clutch basket, changed the springs etc whilst i was there. the starter pinion was only hand tight so I tightened it up and locked it down.

test started it and it ran real sweet, no noises on tick-over

just got to get new O ring gasket for the pet-cock and I'm good to go