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[Tomshayes]

Hi Tim

Thanks for the response

Well I certainly wont be thrashing the Meteor that's for sure as I'm more of a bimbler.

But obviously I would probably open it up a couple of times but will mainly be using the bike for Sunday rides and shows etc. Mainly short distance sort of stuff 100 mile round trip max.. But it will be used by all means.

As you can probably tell I want to make the bike more useable and oil tight without doing anything too radical, just what's necessary.

Would you suggest the rocker boxes should be vented to relieve the internal blow-by pressure?, If so all of them or just the Ex sides and what size vents?

In light of your thoughts on the Crankshaft, and as an extreme option, Is it feasible to fit a SM or Connie Crankshaft into the Meteor cases?. giving the larger BE and the crank pressure relief clack valve. I assume suitable conrods would be needed to go with it!

You say your 57 SM has the std open 7/16" vent from the drive side same as the Meteor,
Did you source the one under the mag on the inner timing case from a Bullet?

Would you be able to e mail me photos of the mods you have carried out?

I know I'm banging on a bit about the problem but as i said before i just want to get the motor right while it's apart!!

Thanks again

Tom

[email protected]

[Barnes]

Hi tom. The 8mm elbow cant dissipate the pressure the the timing chest drilling creates. forget doing that mod it doesnt work. My breather was just installed so that as the crankcase vents to the oil tank the vapours have to cross the oil tank and go up the filler neck before exiting the new breather. Thus dropping any heavy particles of vapour into the oil tank on the way through. All you get then is a slight mist up the new breather that is not noticable. I have so far put 300 miles on my engine since rebuild and the new je pistons with the 3 part oil rings are performing magnificently. It hasnt burnt a drop of oil and the engine has alot more grunt. By all means block the breather at the base of the barrels but go no further. Ed

[Tomshayes]

Hi Ed

Thanks for clearing up the timing side drilling thing.. So to be clear I will not be drilling a hole from tge timing chest into the oil tank but I will be blocking the oil tank breather slot and forming a new oil tank vent from the filler neck.. Now given that I only have the original crank case vent on the drive side as per the Bullets would it be worth while venting the rocker boxes as per Tims suggestion..Any chance you could e mail a PIC of the oil filler vent mod?

[Mark M]

Tom, when I first acquired my 1953 Meteor it had an exhaust rocker cover stud pulled out, a common problem when they've been over tightened. The engine was completely oiltight and burned no oil, at least not visibly. After I fixed it, it started pumping oil from the drive side breather and it's been that way ever since. I use a high mounted catch bottle off the drive side breather and this works well enough. However, replacement of that stud, just 3/16", seems to have made all the difference. I suspect these early low compression engines may need different and simpler breather solutions to later more highly tuned engines but it's hard to say. Draw your own conclusions!

REgards, Mark

[Norm]

Mark This Meteor I'm working on, somebody previously had stripped 3 of the head steady studs, 2 had been tapped out to 3/8th whit,and the third put back in with Loctite. Tapping it to 3/8th opens it in through the rocker chamber above the rocker spindle boss, I'm not sure if this was the case with the original 5/16th holes. What I have done is bore a 3/16th hole through a piece of 3/8th threaded rod and put that back in the existing 3/8th hole and this allows the top end to breath a bit on the left exhaust valve cavity. I'm wondering if this could be an idea to do it on the 4 rocker chambers or if just one would be sufficient, going on what you have found.

[Norm]

Ok so for kick and giggles I have fitted breathers on the 4 head steady studs so I will see how this goes and what amount of breathing is coming out of each breather

[Mark M]

Norm, our Cousins over the pond had a go faster parts supplier called Webbco (?) who made bits for all types of Brit bikes. One of their lines was a set of replacement rocker covers for the Twins. In a set of 4 they are all heavily finned but 2 have a large diameter breather take off point, maybe as much as 3/8", I've never handled one so am only working from pictures. What we don't know is A) what models they were intended to fit and when they were introduced, B) if they were to fit the inlet or exhaust and C) if they actually worked!

REgards, Mark

[Norm]

Mark I have had a slight problem with the stubs I brought up from the head steady nuts in that they just clipped the inside of the tank, bit of ball pien hammer work and they should be good, I'll give it a run tomorrow and see how much they breathe, or if they breathe at all. Only way I can see any crank pressure getting up there is through the oil drain holes in the tappet guides and they are not very big but I guess any pressure relief is going to help

[Tomshayes]

Well as I am doing a full strip measure and rebuild I am going to replace the two rear (ex) head steady studs and fit drilled through 3/8" replacements and give it a go.. Worst case scenario replace with undrilled ones.. A potentially effective and easily reversible mod!

[Norm]

Tom what I did was a piece of threaded rod 40mm long, bored a 3/16th hole through it, them turned one end down to a bit bigger than 5/16th about 12mm long so I could put a piece of clear plastic tube over it.I then juts screwed it into the head, shake washer and a nut and the stub sticking up through the nut. I now have 4 tubes I will run into a catch can under the seat with a single tube out to the rear of the bike. See how it goes