quote:
The oil restricter started with just a brass jet & later changed to the rotating distributer with a hole in the side to index with the oil passage. The hole size was increased at least once, & in 1956 was replaced with a flat. The 1953 should have an early distributor with the small hole, which may be blocked. I suggest you clear it out. Be careful about just replacing it with the later type as they also experamented with oil jets in the cases or heads to control flow. Seemingly, the flat type, while less prone to clogging, passed too much oil to the heads without restrictors. Cheers, Don.
Hello Don,
The bike has an old type oil distributor (small hole only) which I have check several times. I think I will change it with a later model distributor which has the cutout in it. I believe they are much better. I will be happy to have to too much oil up in the top end....I will then re-install the metering plugs I removed in the barrels.
Model 20 Twin Bigend - oil problem
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johnnyb
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Don Madden
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Model 20 Twin Bigend - oil problem
Sounds like a good plan. If you need more oil flow, contact BP for advice. Cheers, Don, who lives near the Torrey Canyon oilfield, namesake of the infamous tanker many will remember.
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Groily
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Model 20 Twin Bigend - oil problem
The oil distributor bush has to be a prime suspect, I agree. But I have stuck with the original type - small hole no flat - since forever and not had a prob. One of mine is a Mod 20, '54 model, and t'other a '53 G9. I've only replaced a rocker spindle once as far as I can remember.
Are the cylinder base gaskets obstructing the top end flow I wonder? I find some gaskets aren't a great fit - in that the hole alignment is poor. (In the case of the head gaskets poor stamping can cause a fair bit of wear on the pushrods too, which can be quite alarming. Although the alloy tubes are quite thick-walled, there are limits! I've replaced a few of them over the years.)
I have kept the metering plugs in the heads too, and no probs. The Mod 20 has done 400,000 km now, so it's a bit like the chippie's favourite hammer with three new heads and four new handles, but still the same old thing.
I'm at a loss as to why, if the parts are a match, you should be having this problem, especially after all the things you've done to try to solve it, and double especially if it was behaving properly before. Maybe the later bush will help, hope so anyway. But - and I don't know as I haven't suffered it myself - over-oiling can apparently be as big a pain as under-! Good luck!!
Are the cylinder base gaskets obstructing the top end flow I wonder? I find some gaskets aren't a great fit - in that the hole alignment is poor. (In the case of the head gaskets poor stamping can cause a fair bit of wear on the pushrods too, which can be quite alarming. Although the alloy tubes are quite thick-walled, there are limits! I've replaced a few of them over the years.)
I have kept the metering plugs in the heads too, and no probs. The Mod 20 has done 400,000 km now, so it's a bit like the chippie's favourite hammer with three new heads and four new handles, but still the same old thing.
I'm at a loss as to why, if the parts are a match, you should be having this problem, especially after all the things you've done to try to solve it, and double especially if it was behaving properly before. Maybe the later bush will help, hope so anyway. But - and I don't know as I haven't suffered it myself - over-oiling can apparently be as big a pain as under-! Good luck!!