My poor old townmate:(

Hello guys.

Jon from Bristol and I think I may be the only town mate cruising the streets of Bristol:)

I bought a t80 last year and absolutely love it. It's in excellent condition and ran beautifully when I bought her. I've just joined this forum as I'm not the most mechanically minded and I have been having problems with the bike.
Firstly It kept cutting out so bought a new Cdi unit and seemed to work ok.
More recently it starts 50/50 and often cuts out randomly. I've cleaned the air filter, adjusted the carb and bought new spark plugs but it seems purely random if it starts and if it cuts out.
I bought a new spark plug yesterday and she started 1st time, went for a ride and today she won't start. The spark plug is pretty black which the manual says the fuel mix may be too rich, but not sure how to adjust this?
I don't want to keep throwing money at her if it may be a more serious problem but am desperate to keep on the road. Any thoughts please?
Someone said it may be the lead from plug to coil? Worth a shot I suppose.
Cheers. Jon

Worth changing the coil but as the spark plug is black it may be burning oil, does the exhaust smoke? The mixture cannot be altered other than at idle unless you change the jets which is unlikely a previous owner would have done that. Or the choke may be sticking closed, check that the cable is free & its all operating smoothly. Other than that it looks like you have covered most other causes. Could just be a clapped out engine.

Sounds like a carb issue and like John as mentioned I would look at the choke make sure its working on and off ok,
is the plug sooty or is it wet and oil looking. I think its some thing silly. Gaz

Hi ya. The choke all seems free moving and the exhaust isn't billowing out black smoke. When being ridden it does splutter a bit sometimes and has a tendency to just cut out when idling. I've had the carb cleaned and it worked for a few days now not so much!
The plug is generally more sooty than oily although where I'm kick staring it so much I'm flooding it. Just seemed weird that it purred with a new plug one day then conked out the next and it was def sooty plug then. Bloody thing. Cheers for input tho lads;) there's a Yamaha dealers not to far away. Got a feeling they will be getting a call soon!

You say you had the carb cleaned who did that? I would start looking at blocked slow running jet and fuel flow pull the petrol pipe off carb end and check the fuel is flowing you will need to turn the tap to prime if it pours out try riding on prime see if its better then, if it is fuel tap diaphragm is dodgy

Carb was cleaned by a car mechanic down the rd. rang a few bike places and no one wanted to have a look. To old apparently! There's good flow to the carb (just had a look and now stink of petrol). Tried taking the plug and lead out and seeing if a spark on an earth and no noticeable spark so I'm wondering if there's some problem with the lead or coil. Does anyone know if the lead can actually detach from the coil or do have to buy both?

jon barton007 wrote:Carb was cleaned by a car mechanic down the rd. rang a few bike places and no one wanted to have a look. To old apparently! There's good flow to the carb (just had a look and now stink of petrol). Tried taking the plug and lead out and seeing if a spark on an earth and no noticeable spark so I'm wondering if there's some problem with the lead or coil. Does anyone know if the lead can actually detach from the coil or do have to buy both?

Lead cannot be detached from coil, plenty on eBay http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2050890.m570.l1313.TR0.TRC0.H0.XIgnition+coil+Yamaha+Townmate.TRS0&_nkw=Ignition+coil+Yamaha+Townmate&ghostText=&_sacat=0

Excellent. Thanks for the help. Will get it sorted eventually

if the plugs is black its running to rich and will cut out because the plug will be to fouled up.
try a new plug then may be the mixture screw needs adjusting on the carb.

I will get a new coil and lead and spark plug them try adjusting the carb again.
Someone said to tune it to get in ticking over then adjust throttle screw so it's revving high and same on the other screw (pilot screw I think) so there both revving high and then ease off the throttle screw until it sounds balanced. Sound about right?

One other thing you should check is that the spring under the plastic cap on end of choke spindle on carb is not broken.
This tensions the choke butterfly in the carb so that it can open up when throttle is applied. Bit like an automatic choke but you have to move the lever back after its warmed up to take the choke off. Unfortunately to my knowledge new springs are not available new, & they are fiddly to fit. The spring on mine broke but this resulted in the choke not closing so hard to start, luckily I had a spare carb & fitted that.
Best to remove the hose from air box & check that the butterfly choke is opening & closing. It could be stuck in closed or partially closed position thus giving rich mixture.

A few questions:

1. Does it cut out when it has been running for a while?
2. When it cuts out, does it even start at that point again?
3. Does it have spark when hot?
4. Have you checked valve clearances?