hello from a state of disassembly.

[Albervin]

think that may end up my next trick bruce. someon has tried to crush seal a piece of tube in there but it isn't working. is it also the vent for the tank and and what methods are recommended to plug it off please?

p.s. is it normal for the upper links of bramptons when plunging to come remarkably close to the control lever adjust nuts? mine were struck once or twice though god knows the manufacturer of the levers as they're alloy. have moved them outboard a tad more for now. the brake cable nipple pulled clean off the cable in the lever so resoldering looks like it might be fun. just the middle of a long winding journey i spose.

When setting up Brampton forks the upper link should be horizontal when you are sitting on the bike. The bottom links should be pointing lightly downwards. They shouldn't come anywhere near the handlebars. Check the poundage on the spring. If you want, send me some close up pics, you have my e-mail address.

 

[lindie]

When setting up Brampton forks the upper link should be horizontal when you are sitting on the bike. The bottom links should be pointing lightly downwards. They shouldn't come anywhere near the handlebars. Check the poundage on the spring. If you want, send me some close up pics, you have my e-mail address.

spring is stamped 160 on i think it was the nut. i read that a 180 was normal and needed for a sidecar but haven't one to hand. it's more the orientation of the parts in movement the bothers me rather than the poundage. though i assume that a 180 with it's thicker(?) wire would bind before a 160 i am thinking the non standard levers and where they had been placed may be more to blame. the tank however is still precarious. i may try and cushion/buildup the steering stops and see how that goes. it's not as if i'll need the lock to go trials or scrambling with it.

 

[timetraveller]

Good day Tom (as Hal might have said). A good place to look for kick start cover leaks is where the shaft, G40 etc, goes through the back plate. When I rebuild an engine I remove the plate, countersink the crankcase and insert a well greased 'o' ring, which is a good fit around the G40, to go behind the plate. This stops oil migrating along the shaft and into the kick start cover. Most of us have blocked the hollow that goes to the primary chain case to take a left hand kick starter and when that does not stop the leaks then the above generally will. Why oil should ever find its way along that shaft, through the bearing etc etc is probably more a matter for an exorcist than a mechanic.

 

[Hugo Myatt]

Chain lubrication

Confused. The standard chain oilers on all my Vins (3 'C's) all lubricate the bottom run of the chain.

 

[bmetcalf]

Confused. The standard chain oilers on all my Vins (3 'C's) all lubricate the bottom run of the chain.

As noted above, I've never seen the oiler in the flesh. Can you post a pic or describe the routing of the tube?

Thanks

 

[Tom Gaynor]

Scott-oiler

I'm sure they have a website.

The device is a cylinder about 1 1/2" dia x 5". This holds the oil. The oil is behind a valve that lifts under inlet suction, so is open proportionate to throttle opening (and closed when the motor is stopped). On the other side of the valve is an appropriate length of capillary tubing that delivers the oil, maybe one drop every 20 seconds, to the bottom run of the chain just forward of the rear sprocket. The feed can be increased for wet weather.
It is quite an unobtrusive device: there was one on my Ducati Monster when I bought it and for several weeks i thought it was some part of the Ducati's under-seat electronics.

 

[Hugo Myatt]

Chain oiler

The chain oiler pipe (A69AS) is a cadmium plated steel pipe of, I think, 5/16” ID fitted with a tapered nipple and a ¼” BSP union nut as used on the petrol tap pipes. The pipe, of approximately 13”long, is steel to avoid fatigue breakage as it is only supported at one end where it screws onto the Tank Breather Adaptor (T 29), which in turn screws into the UFM. The pipe leaves T29 and gently snakes its way down, inboard of the rear carburettor stub then forward of the battery carrier ending in an almost 90 degree curve and nestling in the crease formed between the back of the gearbox and the upper rear gearbox stud boss. From here it projects slightly beneath the upper run of the chain and (theoretically) drips onto the lower run. Often some fettling is needed for if the chain is slack the top run can foul the chain oiler pipe and cause an alarming and mystifying noise that is transmitted through the UFM and is difficult to identify. Although the spares list drawing (M018) shows the chain oiler having a splendidly regular shape I have never come across two exactly the same. It looks as if they were bespoke to each machine rather than made on a jig. The Tank Breather Adapter (T29) is a pesky little critter for though it is easy to screw into the UFM, once the oil pipe has been fitted it is difficult to unscrew the oilpipe again without unscrewing T29 with it. This is because the hexagon on the T29 is at the upper end and shrouded by the UFM and once the oiler pipe is in place it is impossible to get a ring spanner on to T29 to hold it in place whilst you unscrew the oiler pipe. The chain oiler on the Comet is naturally quite a different shape altogether. Series Ds had to make do with just 18” of rubber hose.

 

[lindie]

thankyou for the description hugo. i don't suppose i could trouble you further for a picture of one that gives an angle to see it's routing sort of clearly? what is the discharge rate like in relation to idling. does it drop out a fair amount and would you say it at least oils adequately or does it waste more than it helps?

 

[Hugo Myatt]

Chain Oiler

Lindie,
I have no experience of Series B UFMs which have no restricter valve and in which the chain oiler is merely an open vent breather supposedly delivering oil mist to the rear chain. The Series C has a needle valve PR40 inside the UFM oil filler neck controlled by a small spring PR41. This needle valve is, in fact, a standard Amal carburettor tapered air screw with the spring from the same. Usually the taper is worn to a shoulder from having been screwed down too tight to try to stop excessive oiling and must be renewed if you are going to have any chance at all. Unfortunately over the years the seating in the UFM may have become worn and I personally do not have the skill to do anything about that. It is also possible that at some time through ham–fistedness there may be the remains of a broken needle valve jammed on the seating. Threading a control cable through from the other end can dislodge it but it may fall into the oil tank. Unfortunately being brass you cannot get it out with a magnet. Assuming the seating is clear and undamaged and you have a new needle valve then setting it up is the next problem. There is no point in setting it up with the engine cold and the oil thick for once it gets hot and thins it will gush out at an alarming rate. Gently screw the needle valve down until you think it is just closed. Ride the bike until the engine is up to working temperature but keep an eye on the rear tyre because if you have got it wrong it can quickly soak the tyre with oil. Once the oil is hot you set the valve so that the chain is obviously being oiled but not excessively. In the old days it was said you set it up so that just a few minute flecks of oil appear on the sidewall of the tyre. Originally single grade 40 weight or 50 weight oils made this relatively easy, however, modern multigrades and synthetics with all manner or clever additives complicate the issue. When set up correctly I have found that it adequately lubricates the rear chain (and not the rear tyre) but it is, of course a drain on the oil supply in the UFM.
Because I am digitally illiterate I am unable to supply a photo as yet. However I shall try to prevail upon ‘She who must be obeyed’ who is a technical wiz to get a photo flying through the ether for you.

 

[Hugo Myatt]

Chain Oiler

Sorry Lindie,
Preparing to photo my three spare chain oiler pipes I realised all three were for the Comet. Totally different shape. I am afraid I can not get a reasonable photo of the Twin pipe in situ and I am a bit loath to try to take it off for the reasons stated. However I did notice one of the spares had an Amal Carb main jet soldiered into the business end to restrict oil flow. This was a popular modification years ago.