E: Engine Are Alloy Idlers a Problem?

[rjemielita]

I have opened up my timing chest and been greeted with alloy idlers. I'm a little surprised at this as everything I have seen this far has shown steel ones...... I would guess that these are an aftermarket thing from yesteryear. My gut feeling is that these would be a recipe for oil full of aluminium. Am I being pessimistic? View attachment 53729

I recently stripped (first time since it left the factory) a series D Rapide engine that had clearly been ridden into the ground e.g. the front cams were ROUND not elliptical. This engine has the large alloy idler with little or no visible wear and no alloy chippings in the oil filter or elsewhere in the engine so it will be going back in during the rebuid. If it was good enough for the two Phils its good enough for me.

 

[highbury731]

The alloy idler in my engine was absolutely on the point of stripping teeth. There was a large amount of alloy dust in the big end. The powder was on the point of blocking the oil flow to the big end. It's a moot point which would have happened first, but either could have happened within 10 miles. The bike was ridden right up to the point of disaster, but not over it.
The last tax disc expired at the end of 1960, so the idler is likely to be a Vincent part. How do I identify a genuine factory part or a pattern part's source?

 

[vibrac]

end of 1960's was a bad time for parts. Harpers or coop alman or whoever were getting out and the spares company was not formed until the mid 70's. in between it was bandit country to some extent.

 

[Generic Beardy]

end of 1960's was a bad time for parts. Harpers or coop alman or whoever were getting out and the spares company was not formed until the mid 70's. in between it was bandit country to some extent.

I should be in the clear then!

 

[roy the mechanic]

Alloy idlers can and will cause all manner of aggravation in your motor. The cost of a steel one will be much less than the rebuild if the unthinkable happens.

 

[greg brillus]

Not to mention all the build up of sludge and tiny alloy flakes in the base of the oil tank, its usual final resting place.

 

[Bill Thomas]

So many of us have had that fault, = History !,
And new people think they know better, Got to find out the hard way .

 

[Generic Beardy]

So many of us have had that fault, = History !,
And new people think they know better, Got to find out the hard way .

Seems a rather barbed response considering that I've already said multiple times earlier in the thread that I'll be changing it to a steel one in due course.

 

[Bill Thomas]

Sorry, Getting Old and Crusty,
Not been out on a Bike this year yet .

 

[Generic Beardy]

It's nearly riding weather! The rain hasn't quite warmed up enough