Ariel Arrow points problem

[alanbrown]

I now have my rebuilt Ariel Arrow engine running using the contact breaker points that came with it. Starts up fine and runs well as long as the points cover is not fitted. When I fit the cover starting is poor and it will only run on one cylinder. Inspection of the assembly reveals that both contact breaker springs are very close to the inner edge of the cover, and are probably touching the cover and earthing the ignition when it is fitted.
Could the points and Spring assemblies be incorrect?
Any help appreciated

[alanbrown]

Here's a photo

[iansoady]

I had a similar problem with my Arrow - its setup looks much like yours. I found I had to adjust the position of the cover carefully to eliminate it.

I did try sticking a layer of insulating tape round the inside of the cover but that didn't seem to work for some reason.

It does look as though your condensers may be sticking out a bit further than they should at the terminal end - are the locating tabs in position?

[White.John.A]

Hi Alan, I had a similar problem. I made a wooden spacer to fit under the cover and lift it away from the points. It did the job. Not all together pretty, but it did prove the point.
What has interested me, is your bike running on one cylinder. I have just replaced the points and condensers, as my bike only runs on one cylinder, even though I haven’t fitted the cover yet. I haven’t a clue what the problem is. You have made me consider that the spring on the points is to close to the casing.
John

[Michael.Brown]

Hi John, Ian, Alan,

When I rebuilt my Leader I had only one side sparking. It turned out to be the Contact Breaker Base Plate Screw just touching the Contact Breaker Spring and shorting that side out. Solution was to fit a smaller headed screw and lever the spring away a little (there is a little movement to be had). No further problem in 450 miles using the std setup and parts.

Foxy

[White.John.A]

Thanks Michael,
I will look into that.
John

[Roger James]

Hi Alan,
I've been looking at the photograph of your points set up thinking something doesn't look right, so this afternoon I went down into the shed and removed the points cover from my Arrow engine to have a look at its points set up and have come to the conclusion that the Condensers on your engine are too long in the body, on mine fitted with original old stock Lucas condensers there is more clearance for getting the points cover fitted.
Hope this helps. Have you got any old original condensers in which to compare their length with those fitted to your engine?

Jess

[alanbrown]

Yes, I think that's the answer. The condensers look new, but could be cheap copies of the originals. A shorter condenser would bring the terminal nut in,and also tighten the spring, bringing that in too, to clear the cover better.
No amount of "fiddling" with the current set up has changed anything
I have no original condensers to compare, but I'm sure you are right about this.
Thanks Roger!
Alan

[Roger James]

O.K. Alan,
I would be happy to send you an original Lucas Condenser for you to compare with those on your engine. I can pop it in a jiffy bag, I don't want anything for it. Cant say it is in full working order but at least you would have something original to compare and know it fits more snugly allowing the cover to fit and the type and size of condenser to look out for.

If you want one, send a 'Private Message' with your address details so that they are not on view to everyone reading forum messages

I did take a photograph but its a bit blurred so didnt send it earlier on but its attached now, probably just clear enough to see there is that bit of clearance that you dont have on yours.

Jess

[alanbrown]

Thanks for the offer Roger.
I have just been reading your comprehensive post on another topic, (race/parade/sprint etc)and I was interested to read your suggestion re Triumph points plate ,with better adjustment and remotely mounted condensers. This would seem to be an improvement over the original set up. Where could I get a set of points like this?
Thanks again for you kind offer.
Alan