Re-torque interval

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Hi
What are the recommended re-torque intervals when fitting a new composite head gasket?
thanks
David
 
David,
I guess we all have our own system, bit this is what works for me.
Composite gasket sprayed lightly both sides with VH10 copper gasket sealant, and a thin line of Loctite 574 around the pushrod tunnels and front studs.
I set the valve clearances to 8 inlet and 10 exhaust.
Run the bike for 10 miles, let it cool over night then re torque with the same clearances. Not forgetting to tighten the barrel down first.
Run the bike 50 miles then the same again.
Run the bike 300 miles, retorque again and set the clearances to 6 and 8.
sam
 
Thanks Sam
Its interesting different people's experiences....i had read of one guy who is adamant that with composite gaskets you NEVER add anything else. His point is that the gasket is impregnated with some kind of sealer and that if you coat it you prevent it working as intended. I therefore fitted mine dry. I just hope it holds out!
Your re-torque intervals make perfect sense and remind me of the trident recommended intervals. One guy on NOC says run it 10 mins retorque, then 50 miles and retorque, finished, but that sounds too few times to me.

David
 
I had ongoing troubles with the thick copper headgaskets until I fitted an. 020 composite one and followed a retorquing procedure pretty similar to what Sam describes. I didn't spray the gasket but did add some standard type Permatex gasket goo around the pushrod tunnels.
I dont know if it is just having a good seal vs. Leaking or the little compression boost from the. 020 gasket, but did it ever wake the bike up!
Head and cylinder nice and dry for 3,000 miles now.

Glen
 
The push rod tubes seem to be the biggest PITA, and different things will work I'm sure. I choose to brush a thin coat of Permatex high heat red, gray, or blue around the tunnels with nothing else on the gasket. I torque it and let sit overnight. I always get a bit more the next day. Then I set the valves and run it on the road enough to get all of the engine up to temp, let it cool over night and re-torque. I usually get some more this time too. I repeat that 'heat, cool down' cycle again but the retorque does not usually result in any further cinching. That's it for me.
 
After my rebuild 4 years ago I retorqued my copper head gasket at 500 miles and thats it, have done 15,000 miles since and have had no problem, its just starting to get a little weep at the front now so will retorque it this weekend.

Ashley
 
I always use aluminum spray paint for head gaskets. Never use any "real" gasket sealer. We used it on everything from low compression street motors to 13.5:1 competition motors. Never retorqued them, never had any leaks. Did the same on my Commando when I did new rings/valves/etc several years ago - no retorque, no leaks. I firmly believe in doing what has proven to work so, for me, that's been working since the late '70s when we started doing it at the shop where I did engine work.
 
Ugh, this is like the fast or slow thread, There is no set interval of re-torque as it varies from those who do it once and are fine, while others loose clamp force between the 10 min and 50 mile interval. If'n was me I redo on every cool down I could first 500 miles then 1000 and 5000 mile mark there after plus engine barrel and clamp bolts too. If you are still using a torque wrench and claw foot after first few times then way more disciplined than me who just keeps cranking down till leaks stop and holds or something gives in, like me to break down and tear down to fix ring blow by cause/soruce solution. Metalic paint is hard to beat but by Hylomar and natural fiber thread. JMS lays thin copper wire or un-waxed dental floss. Do not use synthetic fiber.
 
pdl999 said:
Hi
What are the recommended re-torque intervals when fitting a new composite head gasket?
thanks
David
It (composite head gasket) probably wont last long enough to worry about re-torquing. But I would say after the first good warmup for sure then at maybe at around 500, then you should be good.

This should open up that can of worms. Just my opinion.
 
I don't know, cos I wasn't there... but I doubt that the factory ever did anything other than fit - torque - ship and that would have been it until the first 500 mile service.
 
Fast Eddie said:
I don't know, cos I wasn't there... but I doubt that the factory ever did anything other than fit - torque - ship and that would have been it until the first 500 mile service.

True but aren't we talking copper gaskets here.
Copper will not compress with more torque and with truly flat mated surfaces should be no leaks.
However over time and use I think there may be some head warpage that unless resurfaced may make getting a perfect seal with copper difficult.
May seep but not blow out.
The composite gaskets are soft enough to compress, so a re-torque after some running has a chance of continuing to compress it a bit more, reducing the chance of a leak. Probably best bet with an older engine.
My experience with a new composite gasket however was for it to blow out, luckily within a couple blocks of home. Had maybe 50 miles on it without a re-torque. Next one I torqued main bolts at 40ft-lb (35 called for in manual), rode carefully for about 50 miles and re-torqued, however there was no more movement so the 40 seemed to do the job. About 4,000 miles since with no problems. I do run for a few minutes to allow a warm up before applying serious throttle though since iron barrel and alloy head will move a little during warm up.

Advantage of copper is will not blow out, but probably harder to seal than composite, however composite can blow out and leave you on side of road.
 
The flame ring gasket in mine has been perfect so far, only 3,000 miles tho, so time will tell. I could not get copper to seal on this particular bike.

Glen
 
I never had an issue with flamerings on Combat even after reusing couple times, until last one from major vendor in 2006 that just didn't look as robust in the ring - sure enough blew out on mere legal first commute about 10 mile from home and almost burn bike up - stopping within seconds of the jets cutting fully through clear factory fuel hose. I don't not spare the muscle on my torque tasks so just tight alone was not enough in one flamering which until I see better has scared me off to put up with misting oil rather than stranded jet risks. Good rings state and good PVC help a bunch too.
 
My retorque schedule is very similar to Trident Sam's. About 3 retorques spread out over increasing mileages in about 500 miles total. The head gasket should then settle down.
 
This is an interesting discussion about composite vs copper. Hobot's remark about a questionable composite example reminded me of the same issue we had at the shop I worked at a few years ago. Reputable venders were suddenly supplying gaskets that just plane did not fit. 850s only I think. They were too loosely punched and slid around on the block enough that the flame ring could possibly not locate evenly around the bore. It was impossible to tell once the head was dropped if the gasket stayed put. For a while that's all that was supplied by our usual suppliers. They were obviously all manufactured in the same garage and re- packaged with the gasket kits. We got some from Mitch Klemph that were much higher quality in every way. This is what's been in my engine now without so much as a damp spot for 10,000mi or so. I think copper head gaskets are less needy of fussy re-torquing simply because once tight they are not going to relax. I've never had one of these blow out but it can be tricky to seal the tunnels. Sometimes a used copper will have some pretty good witness marks from the previous install and no amount of annealing will heal that so I won't re- use it.
 
The first and very successful first novice install I did was with a robust composite flamerign with substanical metal ring with some type of dry aheasive on both surfaces. that held pressure and oil w/o much re-torque and stayed sealed on Peel's stuck throttle even. The other was a looser looking composite/paper and mere copper foil folded/crimped on the edge of the wimpy base material. I had new copper on hand so instead of wait and risk another blow out through oil drain hole I 'over' annealed the copper and it worked fine until a 1000+ mile trip after only time for two torques but did clamp down again a few 1000 miles more, till ring wear pressure made it and barrel and case seams blow oil out. Its had 4 'over' annealing at least and now think its too unevenly mashed down to use again, but 'over' annealing still softens it to warm wax like softeness when done beyond mere cherry red. I'm told I'm stupid to even report this but me and oxy torch is sticking to the story.
Oh yeah about a decade ago a major UK gasket material supplier to gasket makers was convicted of fraud hurting the whole UK industry by substiting new print to pig poop to be a big cause of the universal public reaction seeing makred parking spot, all they all do that don't they...

Please if anyone knows a source of the real deal Flamering ping as soon as practical.
 
I got a "genuine flamering" from Old Britts and as far as I can tell, it's a genuine flamering.

Installed with a coating of copper spray on both sides. BMW gaskets have the goop; never heard that about Norton's.

Retorqued religiously during the first 2K miles or so, at one heat cycle, then 50/100/200/500/1000/2000 miles. Unnecessary? Likely. Felt good? Yup.

No problems to date. Knock wood.
 
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