Valve seat service now or later?

[Rocinante]

I have just measured all the valve clearances and checked the shim thickness, and the result is semi saddening. Last time I checked the valves was about 4000km ago and all but one intake was at zero or negative.

Now one is at zero, and four of six is less than minimum (0.05mm).
The smallest shim I need is 2.05mm, then two 2.10 and three in mid range (2.25, 2.60 and 2.75).
It seems wear is greater than it would normally be, is it indicating I may have a seat problem?

I have had the head off before, eight years ago after we came back from the North- and South America trip, and all seats were machined with new valves. The seats were shaped slightly flatter to get more contact area with the valves, something which would lengthen the seat life. That´s about 40-50 000km ago

Well, the question now is; is it time to take of the head again or should I get the smallest shim available (I´ve seen 1.95mm shims I think, don´t know if you get them smaller) and run it through this summer and do the big job  sometime in the fall?

I knew this was coming and have new valves and head gasket lying in the garage. So I´m sort of ready...

Advice anyone? Mustang?

Dag

[JetdocX]

I'd try to locate a servicable head.

Been down that road you are on with the valve recession and it sucks.  Mine receeded faster than the 6000 mile service interval to negative clearance (I think it was about 2000 miles, actually).  So you probably won't make it through the summer.

I had Andy at Metric Motors (Houston, TX) cut out my seats and insert softer seats and stock valves.  Seems to have cured the problem for me but it was not cheap.

[Mustang]

I would go ahead and shim em 1 more time and start looking for a serviceable head from a breaker . any head from any of the early models will work as long as it is a t 309 or t409 motor , ie speed triple  daytona , trident , trophy
even a t bird head will work even though they don't look the same .

see if you can find one from a low mileage wreck  bike

[Rocinante]

Why can´t I service the head I have? My dealer says I can, so does a mechanic who is used to fix valve seats on Triumphs.

Dag

[Mustang]

well you can use the same head .........but the seats have already been recut once  and my concern would be like poor JetDocx found out the seats were so work hardened that they pounded a new set of valves to death in just 2000 miles .

I find that using a good low mileage head from a wrecked bike is far cheaper than trying to repair what you have that is all worn out

Tigger 2 is waiting for a new head right now ..I already have the head for it its a low 20k mile head that still has all the shims in the 2.7 to 2.8 range .

have been wanting to swap it out last year but the damn valves are still holding in spec for the last 10,000 miles ..........go figure .
the # 1 intakes got nothing left for shim sizes one of em is at 1.95 and the other is at 2.0  but still in spec for clearance . the rest of the valves are pretty good , the exhausts are still like new and #2 intakes are in the 2.3 range and #3 is in the 2.5-2.6 range
if it wasn't for # 1 intakes being pounded into the head it would easily see the speedometer roll over to zero miles .

[Rocinante]

well you can use the same head .........but the seats have already been recut once  and my concern would be like poor JetDocx found out the seats were so work hardened that they pounded a new set of valves to death in just 2000 miles .

I find that using a good low mileage head from a wrecked bike is far cheaper than trying to repair what you have that is all worn out

Tigger 2 is waiting for a new head right now ..I already have the head for it its a low 20k mile head that still has all the shims in the 2.7 to 2.8 range .

have been wanting to swap it out last year but the damn valves are still holding in spec for the last 10,000 miles ..........go figure .
the # 1 intakes got nothing left for shim sizes one of em is at 1.95 and the other is at 2.0  but still in spec for clearance . the rest of the valves are pretty good , the exhausts are still like new and #2 intakes are in the 2.3 range and #3 is in the 2.5-2.6 range
if it wasn't for # 1 intakes being pounded into the head it would easily see the speedometer roll over to zero miles .

Ok, I´ll do a couple of calls tomorrow to see what´s the right way to go. I have some life left, although it has been receding so fast lately that I worry about my summer trip if I wait too long.

I´ve heard several times over the years I have owned the Tiger that there was a series of engines around 98 that suffered from soft valve seats on the intakes, and that that could explain my receding seats problems back in 2001. Then a mechanic who does cylinder head work and has done so on a lot of Triumphs,  said the valves were the problem, not the seats. Now you say the seats could be too hard, resulting in excessive valve wear, which leaves me more confused than ever. :icon_scratch

Dag

[Mustang]

JD sent his head off to a guy in Texas that cut the old seats out and put in new seats ........I think . Don't ask me how I have no idea , but it was like 1000 dollars if I remember right  :shock:

He has been happy I think

the guy in Texas told him it was not an uncommon thing for triumph heads to do (work harden the seats ) and has been a big source of income for him ........redoing triumph heads  LOL
PM jet doc he can fill you in I can't find the thread right now .

[JetdocX]

I can't find my thread either, but here is a shot of my poor valves the first time:



I replaced the valves, springs and seals, ground the seats and 7000 miles later, the recession was back so bad the bike wouldn't start, got crappy mileage.

Sent the head off to Andy at Metric Motors.  He cut the old seats out and put softer inserts in the head for around $800.  Add the new valves for another $200 and head gasket kit for $175.

http://www.metricmotorcycles.com/HeadWork.asp

New goodness, notice the copper-looking alloy around the valves:


No significant recession has occured since.  (8000 miles ago).

[JetdocX]

JD sent his head off to a guy in Texas that cut the old seats out and put in new seats ........I think . Don't ask me how

Romeo:


and Juliet:

[Rocinante]

I took a couple of phone calls today to my Triumph dealer and to the specialized mechanic mentioned earllier.

The mechanic agreed that hard seats could be the problem, because it´s the valves that wear down not the seats. He has seen this happen on Triumph of most years up until a few years back, although they may come in later when milage gets higher. He´s seen it on a lot of Kawasakis as well, and says the two brands stick out in this regard.

My problem if I want to replace the head is that there are few available in this part of the world. I will probably have to find one abroad. With friends living in Sweden that´s a good place to start. It will take some time though, if I find anything at all.

Maybe ebay from wherever, but I hesitate. Would you buy a unseen cylindre head?

My crank case has actually been broken, literally spoken, for nine years.:)
Both lower rear engine mounts cracked while travelling and is held up by a home made arrangement, solid and made by a mechanic but still home made.

So another option is to adjust the shims one more time and get my Swedish friend, who is a knowledgable motorcycle mechanic, to keep an eye out for a low milage engine. If I find one fine, if not I´ll do another seat job when it´s due time.

Dag

[Mustang]

I will keep an eye out for you on a cyl head . they show up on ebay us from time to time as someone is always parting out a bike for one reason or another

ebay parts .if the seller is reputable their feed back should reflect it .........
a bike that is being parted out because of accident with low mileage would probably be a safe bet for a cyl. head

there was a daytona awhile back just down the road from me aways that only had 8000 miles on it and the head went for only a couple hundred dollars IIRC

if something were to turn up I could help you with the shipping to you from the states which could save some money , but due to the weight involved it could prove to be outrageously expensive

heres a 98 tiger head on ebay now but with 47 k for miles I would be concerned about what you are getting
http://cgi.ebay.com/ebaymotors/93-94-95-96-97-98-Triumph-Tiger-900-Cylinder-Head-Good_W0QQcmdZViewItemQQhashZitem3cab82b52bQQitemZ260575507755QQptZMotorcyclesQ5fPartsQ5fAccessories

[Rocinante]

Thanks Mustang

I just checked ebay in the US and in Germany, and there are a few out there. However, the only one which states the milage is 400 USD for a head that´s done 46000 miles, pluss about 130-150 USD in shipping and 25% VAT on both pluss handling fee over here. It adds up to about 750USD. Even with a favorable exchange rate that´s a bit too much.
And who knows in what shape the valves and seats are.

There´s a Sprint ST 1998 engine just down the road for sale. I can´t squeeze that in can I...

:roll:

Dag

[Rocinante]

One more thing my mechanic said when I spoke to him today, was that if I went with the old head I could give him the largest shims available. The thickest I´ve seen on the net is 3.20mm (http://www.sudco.com/25valveshims.html). He would then machine of the top of the valve stem to get the right clearance.

Hence it would be ready for more than one full millimeter, maybe 1,3 mm even of valve wear before pulling off the head again. If for fun we say that the excessive wear now adds up to about 0.10mm average per 2000 miles (it seems to accelerate towards the end, doesn´t it), it would mean a service span of about 26000 miles or 40000km. That fits in with what I´ve seen so far.

It means I´ll have to pull of the head again in about three to four years. I think I can live with that.

Rough figures, I know, but am I in the ballpark?

Dag

[Mustang]

There´s a Sprint ST 1998 engine just down the road for sale. I can´t squeeze that in can I...

:roll:

Dag

 

Sprint Motor going in



Finished job with Black tiger covers on the sprint motor
you need to swap the shifting drums with your tiger motor or it will shift backwards  1 up 5 down  :shock:



did this on a friends tiger and I thought the sprint motor provided a much smoother ride than the tiger motor , certainly seemed to have more ZIP .......

[Rocinante]

There´s a Sprint ST 1998 engine just down the road for sale. I can´t squeeze that in can I...

:roll:

Dag

 

Sprint Motor going in

Serious? Stupid of me sure, but to reiterate,  I´m talking about the 108hp 955cc injection version that came with the new Sprint ST in 1998, not the old one.

Would it fit right in with the only mod being the shifter?

That would be very tempting, a bit expensive but very tempting indeed...

Dag