Bonneville T100 Won't Idle

PaulCas
They also have an inline fuel filter and may be starting to block.
Ride safe
Joe

 

There is a very outside chance you have an air leak in an inlet boot.

The normal thing is for an air leak to create a high idle, not a low one. However, if that has been adjusted out on the knurled knob then a thorough warm up will expand the metal inlet manifold into the rubber boot, seal the leak and the revs will drop. Counter intuitive but might explain why it takes a little while to present as a problem.

Spraying WD40 or soapy water round the boots and vacuum caps will rule reveal any air getting sucked in.

 

Just as a matter of interest, why is he letting the bike idle for 10 mins ? It's an air/oil cooled bike so letting it idle for so long won't do it any favours.

I would say it's likely to be heat-related so something electrical.

 

Could be a breather in the fuel cap blockage or a coil is on the way out ? Coil gets weaker spark as it gets too hot, the weak spark causes poor running and stalling even at speed ! I rebuilt my motor with higher compression pistons, the coils couldn't produce a big/strong enough spark it produced symptoms similar to yours ! As coil was breaking down with heat, had to cool right down to run properly again.

 

I've just found this little filter, not a mention of it in the Haynes manual. where the fuel pipe goes between the carbs it is inside the fuel pipe where it joins the "T" piece.
I will remove it, and fit new fuel pipe and external type filter from local car shop.

 

Paul Cas.
Didn't I tell you that back in August.
Ride Safe
Joe.

 

I’ve never had a problem with “old” petrol, I’ve often left fuel in my bikes over winter while they have been off road and they’ve always started and run fine when the time comes to get them out again.