My guess is that for the Comet you will need to incorporate a splash guard inside the timing cover. The valve lifter is almost in line with the contact between the large idler and the dynamo drive and is likely to get oil thrown at it. Interesting experiment though.
E: Engine Breather Timing: A long description of a different way (Part 1)
- Thread starter Nigel Spaxman
- Start date
Unfortunately I do not have a picture at hand.
On my comet I made a new spoke with an abutment for a spring to rest against. Then I turned a stepped, threaded bush going from the inside of the timing chest out. The nut on the outside is secured with loctite so the bush cannot fall inside. On the inside I fitted a valve stem seal of a Honda 400cc 4 cylinder 4 valve engine. They have very tiny valves with a valve stem of only 3 mm iirc. With the spring over the end against the abutment the spoke gets pushed through the valve stem Seal and the lifter assembled.
So the seal is actually inside the timing side.
Works great, never had the slightest hint of oil at the valve lifter cable entry.
Bernd
On my comet I made a new spoke with an abutment for a spring to rest against. Then I turned a stepped, threaded bush going from the inside of the timing chest out. The nut on the outside is secured with loctite so the bush cannot fall inside. On the inside I fitted a valve stem seal of a Honda 400cc 4 cylinder 4 valve engine. They have very tiny valves with a valve stem of only 3 mm iirc. With the spring over the end against the abutment the spoke gets pushed through the valve stem Seal and the lifter assembled.
So the seal is actually inside the timing side.
Works great, never had the slightest hint of oil at the valve lifter cable entry.
Bernd
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Most breather designs are a bit bulky to include in the Vincent bikes, same with the BMW type when you have to fabricate a housing for it. In case of deciding on the valve cap place there is not a lot of space around there. I am thinking of welding just an alu hose connector on an old cap and place the reed type in photo below at the highest place in the rubber hose, at the end possibly. So the minimal oil mist will flow back into the engine after using that length of hose for separating from the air. I had same type on some more bikes without adding a canister to the hose but did not need to because no oil was ever found from the exit.
This design is very easy to fabricate, with angle grinder, file and abrasive on a plate. The reed blade is a piece of feeler gauge of 0.10-0.15mm ( 4-5 thou) fixed with a 3mm cheese head screw. The hose is 8mm i.d. or 10 mm i.d., and the valve accordingly, no need to go much bigger. There is only little air coming out as long as the engine is allright and no holed piston inside.
Vic
This design is very easy to fabricate, with angle grinder, file and abrasive on a plate. The reed blade is a piece of feeler gauge of 0.10-0.15mm ( 4-5 thou) fixed with a 3mm cheese head screw. The hose is 8mm i.d. or 10 mm i.d., and the valve accordingly, no need to go much bigger. There is only little air coming out as long as the engine is allright and no holed piston inside.
Vic
Hi Erik,
I don´t think there is a problem to extend the hose from the reed to somewhere below the engine. The amount of air from the valve is minimal so you could shove a hose over the small valve and push another smaller hose into that to reduce it. A stepped hose, so to say, for better cosmetic looks and easier routing. But you could try first without extension in case you decide on the valve cap . Maybe there is no practical oil from there in operation.
Vic
I don´t think there is a problem to extend the hose from the reed to somewhere below the engine. The amount of air from the valve is minimal so you could shove a hose over the small valve and push another smaller hose into that to reduce it. A stepped hose, so to say, for better cosmetic looks and easier routing. But you could try first without extension in case you decide on the valve cap . Maybe there is no practical oil from there in operation.
Vic
Nigel,
Nigel,
Nigel,
Thanx very much, ive done it in now and for 50 odd miles it works like a charm, and away with the horrible Elephant on its side.
took it to the left side rear wheel as per original'ics.
on oil out of it at all, i even wonder if it breaths at all.
i couldnt get the amals; not to leak, so am putting on Mikunis (filed the name off, so they look like amals)
Nigel,
Nigel,
Thanx very much, ive done it in now and for 50 odd miles it works like a charm, and away with the horrible Elephant on its side.
took it to the left side rear wheel as per original'ics.
on oil out of it at all, i even wonder if it breaths at all.
i couldnt get the amals; not to leak, so am putting on Mikunis (filed the name off, so they look like amals)
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Vincent, did you run the breather pipe over the engine as with your elephants trunk? Or does it go underneath. I ran mine under the engine and it still spits out emulsified oil especially when I park it. (like almost everyone else) I have often thought that the up and over the engine way would be best but have not done it. It is hard to find a way of doing that that is not a bit ugly. It is not as ugly as the elephants trunk though. I am either going to do it that way or run it into the exhaust or leave it as it is. Maybe after you have done some long runs you can give another report. I am going to be into the timing chest and both heads off soon so it will be a good time to make whatever changes I make for this up coming season. My cams are worn and I have luckily obtained a set of 105s from Garry Robinson. Apparently they never wear out.
Hi Nigel, indeed i made a strait output rather than use the banjo bolt. They restrict a bit.
And the opening of the hollow spindle axle i pointed downwards.
With a bit of easing the airflow as wel.
Than the tube under the engine to the back. Inside 8 mm all the way
Sofar so well.
No emulsion out of it yet.
Only this morning a bit of clear, yes clear water.
I hope my timing chest will not devellop rust inside.
Cheers
V
And the opening of the hollow spindle axle i pointed downwards.
With a bit of easing the airflow as wel.
Than the tube under the engine to the back. Inside 8 mm all the way
Sofar so well.
No emulsion out of it yet.
Only this morning a bit of clear, yes clear water.
I hope my timing chest will not devellop rust inside.
Cheers
V