In a foul mood....

[Paul in NZ]

Argh! I've been looking at this in a funk and am just now going in
circles fast.. argh!

History.... When I rebuilt the TR6C I did two things 'new'..

1. I fitted a Boyer....
2. I fitted a brand new AMAL...

I've completed probably 6,000 miles and in general the bike runs
bloody terrific... I run it in the sprints and day tripped it 2 up over hill and dale and fanged it on the hill...

But...

Its always been a PIA in town and I just cannot get a solid idle. Its has a nasty habit of killing the engine coming to a halt which when 2 up is an utter pain in the behind. (never used to be this bad)

Now - tinkering with it (in ever decreasing circles) I have checked the compression (all good), set the valves (all sweet)....

Now - last time it acted up I pulled the plugs - sootier than a chimney sweep... Hmm...... Hadn't used the bike much for about 6 to 8 weeks and there was some gum in the needle jet - cleaned the plugs, blew out the jets, dropped the needle - bike ran really well... A bit pingy 2 up going over the hill (hot day) so knocked the ign back a couple of degrees and it ran perfectly - after a hard run, pulled the plugs which were both a loverly biscuit colour...

Tonight - decided to head off and top off the fuel and get the milk bread etc (ok ok it was nice and I felt like a spin) and as I headed home - back to running poorly off idle - can't get a solid idle and plugs sootier than a 50's kids book... argh!

Observation - I never had this issue with my really worn out original AMAL but it's slogged out so?? I'm thinking of re sleeving it?

Actions - I'll order a new filter element / needle / needle jet / float / float needle shut off thingy and fit new plugs. While doing that I'll check the float level (again) and staticly check the timing is within cooee (it seems to prefer a touch of retardation)

Question - what the heck else is escaping me?

[tri boy]

You said you refueled, is that when the fault reoccured, or was it playing up prior to the top up?
I'm picking you use the same fuel and supply company most of the time.

Can't help you with the Amals. Never got my head around the various charactor traits they have.

[Paul in NZ]

You said you refueled, is that when the fault reoccured, or was it playing up prior to the top up?
I'm picking you use the same fuel and supply company most of the time.

Can't help you with the Amals. Never got my head around the various charactor traits they have.

Moisture I could deal with... Why so rich though? But yes - usually BP 98 - same station...

Don't be scared of amals - simple things

[riffer]

Sounds to me like there's not enough lead in the fuel for the poor old dear...

[limbimtimwim]

Moisture I could deal with... Why so rich though? But yes - usually BP 98 - same station...

Considering the price of petrol, 98 might not be selling very well and the fuel has gone bad...?

[Motig]

If your bike is hard to start and fouls plugs- the boyer ignition can cause this symptom if you have the coils wired in parallel instead of in series. Dont know if thats whats happening to you but that came from www.oldbritts.com/boyer

[FzerozeroT]

carbs getting too hot in town with limited airflow, would give richer mixture therefore black plugs. Jimmy up a duct to direct air over it and see if it helps.

[Motu]

I take it the Boyer doesn't use the mechanical advance? If it still has mechanical advance I'd be looking there.Weak springs,strong springs,sticky....whatever - it changes for no reason and that's where I'd be looking for inconsistency.+ or - ground? Doesn't matter,but make sure everything is one or the other.Last Triumph I had a play with was a mix match.Boyer you can switch +/- I'm sure.Grounds.....didn't do too good a paint job did you?

Did you get a MkI or II Amal? I know nothing about MkII's....and know for sure MkI's are shit wrapped in crap.Check for slide wear,they flog out very quickly and get air leaks around the slide,completely stuffing up the idle....next time you stop it sits in a different place and is all sweet again.Get the body bored and a stainless sleeve fitted on the slide.

If all else fails I'll give you a couple of hundred for the shitter....

[Doogle]

How long between rides is it?Is it possible that the fuel is sitting in your tank too long and going off?
If what the poster above suggests doesn't work try buying 20l of avgas and running the bike on that.If it settles down then you've found your problem.

[imdying]

Don't know much about old carbs, but having a shit time in the garage is something I can relate to. I hope that you're having a better time of it now.

If you need it resleeved, I've seen some incredibly sleeving jobs done by CBC her in chch, in stainless steel... it wouldn't surprise me in the slightest if this was in their range of capabilities, but I'm picking they would want to see it.

[Paul in NZ]

Yeah, this is annoying all right...

Apparently the new AMAL's have an issue in this regard (holding a good idle) due to a faulty drilling in the idle cct which can sometimes be fixed by re drilling... However - not sure.... Its seriously rich at idle / off idle - say 2,000 rpm in 4th (pootling speed)

The Boyer is connected correctly (in series with 6V coils) and it uses electronic advance - earths everywhere - clean power - battery is good - problem seems independent of ignition settings.

I'll sus it eventually - it just annoys me... bah!

[Paul in NZ]

If all else fails I'll give you a couple of hundred for the shitter....

Bugger off - a new ceramic toilet costs way more than that.... ;-)

[Fatjim]

Sounds like a vtr with a blocked breather hose.

[Paul in NZ]

Sounds like a vtr with a blocked breather hose.

Actually - thats not daft - I'll check the breather tonight. Thanks

[vifferman]

Sounds like a vtr with a blocked breather hose.

Yeah, that was a goodun (not!)
Even road spooge on the end of it is enough to inhibit the ("solely by gravity") fuel flow. And those 48mm carbs sure do have a prodigious thirst.