Tinning bushes etc.

[twolitre]

After offering a suggestion about tinning a bush (in the next post) I thought the following might be interesting.
I was alarmed to find that I could rock the cam in the distributor of my Triumph 5TA to produce a points gap variation of over 10 thou. Even though the bike started and ran well.
I expected the drive shaft bushes to be worn; but not so! It turned out to be that the sleeve of the cam was wobbling/rocking on the spigot of the main shaft. Searching on the web etc. produced no source of replacement parts. PROBLEM!
I decided I had nothing to lose by trying the tinning remedy. I tinned the spigot with a coating of Tinmans solder (I thought Plumbers solder too soft) and eased the coating in the lathe with fine emery paper to get a nice sliding fit
Result? I now have less than 2 thou rock, a more stable tickover, but no improvement in performance. Or so I thought until I found out I had gained almost 20 miles per gallon!
Only time will tell how durable the remedy is, though I think as long as I remember to put couple of drops of oil in the top of the cam every points check it will probably see me out. 700 miles around Wales last week has produced no change.
In any case, if necessary it is not a major job to repeat the excercise.
Jim.

[Marky]

Hi Jim
Good info to know - the more people like your goodself post on here the better, as it gives everyone (like me who doesnt have the sufficient ''knowledge'' or a lathe yet!)  an insight to remedies they may never have thought of! 20 mpg is a major saving these days let alone the mechanical benifits.  Cheers .

[33d6]

Personally I think tinning went out with button up boots although I agree desperate problems bring desperate measures. Nevertheless, Loctite make a broad range of products primarily aimed at fixing problems like this and are quick simple and easy to use. Why tin when you can Loctite? Plus Loctite is easy to clean off.
I think I've spent so much of my time fixing up the mess after bodges like tinning, centre punching and the like that it makes the hair rise on the back of my neck when I see it.
The worst of the lot though is the  bloke with a welding torch. What some people do with a welding torch doesn't bear thinking about. My worst was the bloke who stripped the timing side L/H thread on the crankshaft of an early Matchless single so bronzed the timing pinion back in place. He then managed to do the same to the crankshaft nut on the driving side so had bronzed that back in place also. The result was an engine impossible to strip down. As any early engine is precious it took a long time to get it apart without doing further damage.
The message from all this is, if you do a job, do it right. Don't make life a misery for the next poor sod of an owner.
Cheers,

[Rex]

Broadly speaking, I'd agree with that, and there are some excellent Loctite products now.
My personal rule is not to modify major irreplaceable parts unless absolutely unavoidable, so I would never pop-mark loose shafts or braze on gears etc, but tinning a loose bush is perfectly acceptable as it's quick and easily replaced at a later date and does no harm in use.
Bodgers (either through lack of money or skill or both!) have always been around, even more so when our old bikes were just a method of getting to work, but I would never class the ancient engineering practice of tinning in that class..

[twolitre]

Well now, 33d6. Tell me where I can get swiveling Locktite which will allow the cam in the distributor to advance the ignition and I'll give it a try!
If you know of a better sensible solution I am always willing to learn.
Personally, using Locktite for anything other than precautionary thread locking comes into my category of bodging. Using it on items such as bushes which should be an interference fit also interrupts heat transference which may be important.
Jim.