E: Engine Comet Mongrel
- Thread starter Cyborg
- Start date
Thank you..... this is version 2.0 not quite what I wanted, but felt the need to move along. The first go was a little shorter and was supposed to have eccentric chain adjusters, but got a little ahead of myself and welded the arms and cross braces together before I welded on the round sections for the adjusters. Of course they warped slightly and then I had no way to true them up because it wouldn't fit in the mill. This one above is from a BMW 650, and just needed the swingarm pivots trimmed, another cross tube to support the added shock mount, chain guide, bushings, and some tabs rearranged. I've since replaced the cross slide on the lathe, so could fix the other one by bolting it onto the new slide, but setup would be painful and spring is approaching.
In keeping with my habit of turning newly assembled engines over by hand, I discovered that the intake adjuster nut was just coming in contact with the ET24 inspection cap. The cap is new from Coventry and I believe they are the same from VOC spares. The new caps are machined differently and have less clearance than the originals. This probably doesn't happen very often, but thought I would mention it. I chucked the cap in the lathe and removed some material with a boring bar and cleaned out a bit more with a Dremel. Also took a few thousandths off the top of the adjuster and rummaged around and found a inspection cap gasket that was .040" thinner. The first photo shows the old style cap ..... the area in question is concave and the new cap is just cut on an angle (beveled) between the black and red mark. Mk2 cams and decent vale seats. #fettle
Is this unusual or am I missing something?
Is this unusual or am I missing something?
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This is what's known as "fettling", a very common pastime with a Vincent!
It's the same with Old Bikes and Old caps, Ron and me have just done a Twin, For a Friend of Ron's, We had to swap pushrods around, But still I had to grind the top off and make 2 flats at the top, To turn the adjusters.
There are Special adjusters you can buy now, To fix the problem.
We should all make sure we keep the same pushrods, adjusters, followers, etc in the same place as we take them off, When doing work on our Bikes. Cheers Bill.
I'm fettling my life away.
I did wonder about those adjusters listed on VOC Spares, but wasn't sure they would be any shorter. It seems "fettling" is the preferred route these days. Pretty much everything I order ends up sitting in customs for a month or more. I might have got away with just machining the new cap and a thinner washer, but took some off the adjuster just so there is a little more room when things start thrashing about. I also wondered about the bushel of inspection cap gaskets I have. I don't know their history and they are about .134" thick and as mentioned, I was able to find one hiding in a box that was .040 thinner so used that.
We have checked a lot of Caps, Old ones, And no 2 seem the same, We didn't have time to send off for the new Adjusters, And I have done this mod' on my bikes for many years.
I think it comes down to the fact that these Bikes are hand built ?.
If a new spare part was good for one Bike, It might not for another, That goes for all parts.
Cheers Bill.
I think it comes down to the fact that these Bikes are hand built ?.
If a new spare part was good for one Bike, It might not for another, That goes for all parts.
Cheers Bill.
I would have expected a THICKER washer to give more 'head' room inside the cap.