Triumphrat

03-24-2006

Hi to you all,

I'm a newbie in need of help.
Can someone explain me what to do when you can´t set the clearence (there aren´t smaller shims).
Must i replace valves??Anyone had this problem?

Thanks

tango · 03-24-2006

You need to remove the shim, it may have thickness stamped on it, or measure the thickness and get another one of the suitable thickness to make up the difference.

By the way welcome to the forum.

[ This message was edited by: tango on 2006-03-24 12:33 ]

03-25-2006

Hi David,
Thanks for your reply.I think you didn't understand me. The problem is restricted to one inlet valve.I already replaced the shim with the smalest one there is (200).This tells me that the valve is sinking to much.I don´t know if the problem is in the valve or if it is in the cylinder head (I know the bike had some kind of trouble 8 years ago, but i don´t know what it was).
My greatest worry is the cylinder head....

tango · 03-25-2006

I'm assuming your '96 tigger is the same layout as my 900 Trophy with over bucket shims. If it is then there is NO adjustment, it's a case of measuring the gap, which you have done. I don't know off hand what the gap should be, but take note of the gap remove shim/s and replace with one of the correct thickness to make the gap what it should be.

It may well be the case you've dropped a valve, in which case you'll need to remove the cam/s and the head and remove the offending valve. Check the valve seat for wear or pitting, renew the valve stem seals and possibly even the valve seat and valve itself. Then you'll need to lap in the new valve

It's usually the exhaust valves that tighten on these engines.

The other thing to check is the camshaft, make sure there is no excessive wear on the cam lobe. If there is then you'll need to replace the camshaft.

03-25-2006

Hello again Davie,
Once again thanks for your reply!
The clearence is about 0,8, but it should be between 0,10 and 0,15.
I will ride it for a while and try to get some time so I can do the JOB.
I suspect it´s worn valve seat. The question is...New head or there is something that one can do about it?

By the way, I do think that my engine it´s the same

Thanks
Tiago

peakbonnie · 03-25-2006

It does sound like you've got a worn valve seat, or a worn seating face on the valve itself.
If you are sure that you have less than the minimum clearance, then you will need to remove the head. Its possible that the valve has "mushroomed" and the seat itself is OK, or that the seat has worn.
Either way, I would personally have all the seats recut by a specialist, and fit new valves.
Before you spend money on the head, first check that the valve guides and cam bearings are all OK. Also check that you can't get a good used head for less money, for instance from Triumph-ant Motorcycles: Link
I would NOT advise that you do a single valve, as you could then end up doing the same job again in 6 months!
Good Luck.

nortoncharlie · 03-25-2006

A friend had a similar problem on his Tiger, He took the shim to a friends machine shop and surface ground the bottom (NOT THE CAM SIDE) of the shin to get him in spec. This is not to say you don't have a problem with a sunk seat or stretched valve stem. But it will get your valve clearances back in spec.

nobby400 · 03-25-2006

Quote:

The clearence is about 0,8, but it should be between 0,10 and 0,15.

Have you got that wrong?? if it's 0.8 then you need a thicker shim or is it 0.08???

If it's 0.08 you have a problem with 2 causes

1. The valves seat is wearing back into the head.

2 The cam bearings are badly worn.

If the valve has mushroomed or the cam is worn it will make the clearance larger not smaller like your problem.

peakbonnie · 03-25-2006

When I said Mushroomed, I was referring to deformation of the head of the valve, leading to a similar effect as a worn valve seat. i.e. a reduced valve clearance.
As opposed to mushrooming of the valve stem end which would of course lead to a larger clearance.

03-26-2006

Hi again,

First of all i did a posting mistake.the clearence is 0,08 and not 0,8....(Thanks nobby400).

Peakbonnie, I agree with you.I must remove the head and see what is happening.I hope it´s the valves.(only two of them are this bad and they are both on the 3 cyl).
My plan is to do this the next time i stop the bike (6 months).
After this, I will take the head to a specialist.

I will check the cam bearings, but I think that's not the problem because I only have problems with 2 valves ( the others have the clearences ok and they all have bigger shims like 240)

nortoncharlie,I think that solution will have the camshaft lobes slaming the caps and not the shims...but thanks anyway

Thanks to all you guys (And sorry for my english)