Britbike forum Forums British Motorcycle specific Brands Triumph bulletin board Rough idle

On my 67 tr6c, I noticed the idle is getting a little rough. It’s a ET bike. Carb is only has about a 1000 miles on it. I use stabil in it , gas tank is clean. Besides the idle it runs great.
It idles but it stumbles a little.

as the points heel wears ,
the points max gap decreases .
and retards the timing .

It wouldn't really expect this in a thousand miles ,
but if the felt wick on the points cam wasnt oiled ?
... or if the points arm is Thermo meltable plastic ?

anyway , check the points arm
ponts Gap and the points faces for pitting
and oli the felt .

gapping and timing, even more so with ET than normal points ignition.

The 2 sets of points rely on each other for good operation.

I’ll check the points. Thanks.

Be nice to find a set of NOS points.

Clean the pilot jet. Miles don't matter time sitting does. Even with stabil they can clog..

Hi Mori55, Always start by verifying ignition is correct first. Start by cleaning points. Then check timing. If point gap has changed the timing will change.

Worn rubbing block will close gap. This will retard timing. Not exactly one to one, but .001" gap change is approximately 1 degree timing change. As point face wears it can make pit in one face, pointed area on other face. This also can change timing. Not properly greasing point cam & rubbing block will result in rapid wear of rubbing block. Lubricam SL-2 point cam grease is very good & will reduce rubbing block wear. With good not worn ET AAU & cam with good lube you can expect good operation 1000-1500 miles. Even the modern Daiichi ignition points lasts very well.

Verify timing is correct in every case. As was stated with ET ignition timing is critical.

Then move to checking carb. What carb are you using, I can't recall.

Whatever carb, the idle jet must be clean. Start by marking mixture screw. You know where it used to run well? Mark & screw it in so you can return screw to good place. Then remove screw. Shoot carb cleaner into hole. If possible blast hole with compressed air. To clean better you'll need to access bowl. To really clean carb must be removed, unless you have Premier Concentric.

I know the ET bikes can be temperamental, but properly adjusted they run well & reliably.
Don

NOS 4CA points , at a fair price
https://www.ebay.com/itm/371706047818

389 mononbloc. It’s fairly new.

I put the 6ca points plate in when I rebuilt it. Easier to adjust and the née conensers didn’t fit right.

I used to run a 4Ca plate on a single .
i made up a dummy condenser by gutting an old one and filling it with epoxy .
( cuz as you know , the stud Mount is still needed for the electric connection and spring mount )
now any condenser can live up by the coil , like the 6ca does .
This doesn't solve the points still being fiddley
but does " upgrade" the condenser part .