Triumph Rat Motorcycle Forums banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Bike of the Month Challenge!

1 - 8 of 8 Posts

·
Registered
Joined
·
657 Posts
Discussion Starter · #1 ·
I have finally got around to check my valves. Measured clearances and results are a little surprising. All intake clearances are exactly 0.17 mm (I can squeeze in 0.15+0.02 feeler, 0.15+0.03 doesn't go in), and all my exhaust valves are at 0.30...:confused:
So 2 questions to those learned in this art:
- is this possible to get such uniformity?
- should I try to re-shim exhaust valves - still within spec, but on the upper edge - or just ride it until 24k service?

Let me explain my use of feeler gauge... As I'm anal, all the measurements were take with feeler going in very, very tight, until nothing more can get in. Should I relax a little?
 

·
Premium Member
Joined
·
1,568 Posts
So 2 questions to those learned in this art:
- is this possible to get such uniformity?
Only if you believe your own eyes!

- should I try to re-shim exhaust valves - still within spec, but on the upper edge - or just ride it until 24k service?
It's within spec! Leave well allone. Note the mileage and the measurements: At the service interval check it again, you'll get a feel for the rate of change.

Let me explain my use of feeler gauge... As I'm anal, all the measurements were take with feeler going in very, very tight, until nothing more can get in.
Ease off - don't force the next size. If you can feel resistance as you slip the gauges in, you're done.

Should I relax a little?
Yes.
 

·
Registered
Joined
·
1,784 Posts
I'm fairly anal about mine too and had them all set even to 1.52mm and 2.54mm. I had several out with the worst being 2.54mm (inlet) and 3.56mm (exhaust). It'll be interesting to see how they are when I get it done again in 7000km time (30,000km).
 

·
Registered
Joined
·
657 Posts
Discussion Starter · #4 ·
Thank you, gentlemen. I was already leaning towards just putting the engine back together, just needed a little nudge. I'll make record of what I got and let it go until 24k (probably next spring).
Now the joy of putting it back together...
 

·
Registered
Joined
·
151 Posts
With the exhaust being on the upper end of the spec, I would leave them alone. You might loose a bit of performance and have some valve ticking at cold start-up, but basically that's the good direction to go out of spec.

If you have a tight valve lash, the bucket rides on the base circle of the cam which breaks down the oil film, and you end up burning out the bucket. Doesn't get noisy until after the damage is done.

If your really anal...... like some of us. Mic your feeler gauges to get the exact thickness, and remember that day to day you will vary 0.001" on your "feel".
 

·
Registered
Joined
·
359 Posts
valve clearances

I have finally got around to check my valves. Measured clearances and results are a little surprising. All intake clearances are exactly 0.17 mm (I can squeeze in 0.15+0.02 feeler, 0.15+0.03 doesn't go in), and all my exhaust valves are at 0.30...:confused:
So 2 questions to those learned in this art:
- is this possible to get such uniformity?
- should I try to re-shim exhaust valves - still within spec, but on the upper edge - or just ride it until 24k service?

Let me explain my use of feeler gauge... As I'm anal, all the measurements were take with feeler going in very, very tight, until nothing more can get in. Should I relax a little?
How many Km's or miles has you're bike down ?
 

·
Registered
Joined
·
39 Posts
With the exhaust being on the upper end of the spec, I would leave them alone. You might loose a bit of performance and have some valve ticking at cold start-up, but basically that's the good direction to go out of spec.

If you have a tight valve lash, the bucket rides on the base circle of the cam which breaks down the oil film, and you end up burning out the bucket. Doesn't get noisy until after the damage is done.

If your really anal...... like some of us. Mic your feeler gauges to get the exact thickness, and remember that day to day you will vary 0.001" on your "feel".
Just a thought here, and not trying to teach people to suck eggs but when using feeler gauges there should be a slight drag to the feeler when removing it from the shim pack, akin to a knife through buter. It should not be tight.
I'm not sure what the actual clearance specs are on a speed triple but on race bikes we try and keep them at the upper level of the spec range, and to keep all the same clearance even to the point of lapping shims to ensure this. This also ensures a good oil film as already mentioned.
Vlave clearances will normally decrease over time as the valves and seats wear, so another good reason to be on the upper side of the spec range.
 
1 - 8 of 8 Posts
Top