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Allan G, gavin eisler, Hugh Jörgen, MarksterTT, mondtster, Stein Roger
Total Likes: 13
Original Post (Thread Starter)
#794267 12/30/2019 2:31 AM
by reverb
...hello; the other day I took the road to test the new EI. The gremlings appeared all at the same time. At 12km engine shut off. I had a short circuit that still I do not know where is it but after burn 3 more fuses and checking plenty of wiring I managed to start again and continue on the road.; then in a town at 30km after a stop to buy electrical stuff the engine started with that mechanical noise and just do not start first kick; sometimes second kick or several kicks with some fumes from the carburetors and burned oil odor.
Today I had time to check. The noise seems from the rockers or like a valve trying to grip there. Kind of screeching or shill noise and persistent after warmed up or plenty of km.

What I did:
-inspected the exhaust rockers and all is ok there.
-put oil there
-removed the lines to the rocker boxes to see how much oil is coming.
-kicked to lubricate (I have a rotary pump) with the engine shut off and without the spark plugs. Last year I put the washers the supposed way ( like Mr Healy says) for the 79s.
-put a finger in the return line hole to the reservoir with the engine working to force oil there

I have oil coming and going.
All the valves open and closing with normal kick action.

Still plenty of noise. Also I have another kind of noise from the camshaft/s and some inside the primary (tomorrow I will try to remove the primary cover (is not easy with the rear sets and I need to make another gasket...)

Incredible but the moment before I removed the surefire; the bike was ok...

May be any of you guys can suggest another procedure.

If a valve wants to grip there I did about 65km since I perceived the noise. Seems that do not want to lubricate or cooperate? PO told me that they are black diamond but I do not know for sure.

Liked Replies
#801862 Mar 18th a 11:00 PM
by sloppyoil
Jeez, sometimes an individual has to understand that you cant make sugar otta $hit.Get another head and quit beating yourself up.
3 members like this
#818730 Aug 4th a 07:48 PM
by koan58
Hi Reverb,
The way I see it is that with one gasket the engine will not turn over, so there is negative clearance between pistons and head. One or both pistons are contacting the head in some place(s) before reaching TDC.

I don’t see any way round it, you need to find those contact areas (by claying or blueing) and easing the head surface as indicated (whether that be at the squish band or the filled flanks, as required).

The head will then accommodate the ordinary piston shape that you are able to purchase, but will have minimal clearance (insufficient to run safely).

I would then build the engine with 2 head gaskets and clay to see what the valve/piston clearance is.

I can’t remember if the old pistons had their valve pockets altered (depth or width), whether the valves are bigger than std, or whether the cams are higher lift than std.
The deck may have been lowered, the head surface is almost certainly shaved.
All of these elements may result in piston/valve clash and so it should be checked.
Using 2 head gaskets will reduce such a likelihood.

I would prefer not to go down the route of turning the piston squish rings flat, for reasons in an earlier post. The head squish ring should match the piston.

Best of…
2 members like this
#801155 Mar 14th a 01:55 AM
by desco
You have wasted more than enough time and money trying to get this miss matched pile of parts and modifications to work. The closer you can get it back to stock the better. I have thousands of hard miles on basically stock Triumphs. You got a deal on this bike because the original owner couldn't get it to run either. Time to buy a stock bike or an old Ford Falcon to get around.
1 member likes this
#801601 Mar 16th a 05:16 PM
by mondtster
Reverb, in the amount of time that has elapsed from the start of this thread until now, you could have sent the head to the US, had it properly repaired, and sent back. Yes, it would cost money but what doesn't, and your bike would be at least halfway back to being on the road.

If you want to continue to try to get it fixed locally, I'd suggest becoming a head repair expert yourself so you can dictate what you want done. I just scanned this article but it looks like a good place to start.

I'm going to disagree with the previous poster's suggestions on where to find good welders. I've been largely unimpressed in the ability to weld aluminum alloys with guys from those professions. I would however consider seeking out someone who does aircraft engine repairs. It is very common to weld aluminum crankcases and cylinder heads in this industry, and you'll find things that have been repaired that looked totally destroyed when sent in.

As far as I'm concerned, the head is only half your problem. The other half is the broken piston you have. I think it is now clear where at least some of the difficulty was coming from while you were trying to tune it.
1 member likes this
#801610 Mar 16th a 06:31 PM
by Stein Roger
Stein Roger
I too have been following this from a distance.
Forget that head, it's scrap. Even if you manage to weld and machine it to some sort of usable condition I bet you a cylinder head it's going to give you trouble again. Lots of it, and very soon.
I don't have a T140 cylinder head, so I can't offer you one, but someone on here may have, or know of one. Chances are that this someone may sell it to you at a reasonable price, and send it to you as a gift with a value of $5,- to dodge your import duties.
It can't hurt to ask around.

Good luck!
1 member likes this
#802461 Mar 23rd a 03:53 PM
by John Healy
John Healy
"xxxxxx at some point says that they lubricate the rings and bores and that dry stuff is just internet folklore. I rebuilt lubricating the stuff and I never had an engine smoking.
They say to use conventional mineral oil. I did it that way with the other engines. Also I read yesterday in some other important webpage (I do not remember right now) that better not to use break in oil on the rings..."

Drier assembly of the rings/bore, has been around since the early 1990's. I first used this method when were were doing big bore kits for Kawasaki and Honda 4 cylinder models. MTC is a major supplier of HIGH performance pistons and rings for Japanese motorcycles.

We were machining and assembling these engines as we had been doing before the introduction of federally mandated "energy saving" oils in the 1980's. Neither API SG or break-in oils were available and we had to use one of the "Energy Saving" oils. The engines would smoke so bad as to fill the shop with smoke on start-up that you could barely see anything in the building. We were also having similar problems with total seal type rings.

When I say NOT DRY this is exactly what it means: the bore is washed with hot soapy water until it is clean. When you think its clean keep going for another 5-10 minutes. Then put oil, or automatic transmission oil, on a clean WHITE lint free rag and wipe the bore until the rag comes out perfectly clean. THIS fills the cross hatch grooves with and OILS THE BORES SO THEY ARE NO LONGER DRY!!!!!!!! There is about the same amount of oil on the bore as you would find in a running engine. Then lubricate the wrist/gudgeon pin with assembly lube. Dip your finger in some of the oil you are going to break-in the motor and lightly lube the thrust faces of the piston.

When reading the MTC's tech pdf remember the 280 grit plus is for their coated ductile iron or steel rings in cylinder bore dimesnsions that are held to .0002 inches!. If you are using grey cast iron rings using anything smoother than 220 can be problematic. Coated rings require a tolerance of .0002" for the bore diameter and length. For most British cylinders, especially Triumphs, this is hard to achieve. The factory used, and recommended 150 grit stones. Most of the Triumph builders are holding their bore dimensions as close to .0005 inches and a 180 to 220 grit. It's all about being straight, round and true (right angles to the crankshaft). This typically means boring on one day and waiting for the cylinder to relax and honing a few days later.

It's not DRY, it is drier and not folk lore.
1 member likes this
#802524 Mar 23rd a 10:16 PM
by John Healy
John Healy
The most popular hone used in a lot of shops is the Sunnen AN110 series portable hone. I have a Standard and a Junior. They use the AN series stones that run from AN100 (70 grit roughing), AN200 (150 grit finishing), AN300 (220 grit medium finishing), and AN500 (280 grit Extra Fine Finishing). Grit refers to the size of the stones that make up the honing stones.

In the real world of modern engines it is the RA number that counts. "The finer the grit size, the smoother the finish. The average roughness of the surface is called “RA” and is typically specified in microinches (one microinch is one millionth of an inch, or 0.000001″)." Also with modern engines you have to deal with RPK – the peak height; RVK – the depth of the valleys; and RK – the average core roughness depth based on the RPK and RVK measurements. A surface with a low RK value will have long life characteristics.

A AN200 grit stone will give you approximate RA of 45 micro inches, AN300 approx. 32 Micro inches and AN500 approx. 20 micro inches. Then you get into Plateau honing where you have to calculate how much you need to remove from the bore with a plateau hone after honing. They have a formula for that, but you can forget most of this with our engines.

We have used Sunnen AN200 stone set, wet for the past 30 years, and dry before that, on Triumph cylinders when using grey cast iron rings. Especially WHERE WE ARE NOT INSTALLING THE CYLINDERS and are not responsible for break-in. If we are doing the assembly, and break-in, or the customer is using coated steel or ductile rings we use a 280 grit stone wet.

You would never use a 150, or 220 grit stone when using coated ductile iron or steel rings. You would only use these grits with common grey iron rings!!

We are also in the habit of looking at the riding style of the rider, and how we expect the bike to be broken in. When finishing a cylinder we know is going to be raced I feel that I can use the highest grit recommended for the rings being used. If it is Jerry Wood I know the rings will be seated by the time he gets to the end of pit out. Then again if the customer is approaching his past due date, and I know he is going to baby the engine, I select a grit toward the the lowest recommend for the type of ring being used.

There is no one way that fits all customers and components. To me its like fly fishing where you have to "match the hatch" if you expect to catch any fish.
1 member likes this
#817165 Jul 23rd a 02:54 PM
by triton thrasher
triton thrasher
Originally Posted by kevin
they used to say just put the piston at TDC and tip the motor until the spark plug hole is up. then fill the combustion chamber with light oil from the burette to get chamber volume.

that would work only with flat top pistons tho, if you were then just adding swept volume to get total cylinder plus c. chamber. to get piston dome volume youd have to do the bump-the-pizton-on-the-plate thing and then fill the cylinder

Seeing how much fluid it takes to fill the combustion chamber at TDC works just fine with a domed piston.

Compression ratio is still (swept volume + combustion chamber volume) / combustion chamber volume.

Combustion chamber volume is the space above the piston at TDC, no matter what shape the piston is.
1 member likes this
#817626 Jul 27th a 12:54 PM
by triton thrasher
triton thrasher
It’s the Salvador Dali cylinder head.

[Linked Image from]
1 member likes this
#817735 Jul 28th a 05:10 AM
by NickL
If you are not able to get a thick gasket made have you thought about using several
base gaskets or even making one up, say 1mm thick, aluminium sheet it's common enough.
Filing and opening out head gaskets is a bit fiddly but a dremel type tool can be used.
My own t120 is at +0.100 and i had to file the head gasket out to suit.
I would still use a fly cutter and cut 2 rings into the barrel and set 2 rings of 1mm wire in there,
cut the rings say 30 thou deep and that will stop the gasket moving. It was not an uncommon
practise on race bikes.
I think you've made a good job of the head surface.
1 member likes this
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