Drunkn Munky wrote:lol where abouts are you?

In Hell

aka

Farnborough Hampshire

The easiest way to see if the rear carbs have fuel is to unscrew the drainscrew on the carb (can do it with them on)

if fuel comes out its getting fuel.

Have you connected vaccum balance gauges to the engine?

If the carbs arn't balanced properly the pipes will warm up at different temps.

(can test for this besides the bike idling rough) warm the bike up with the revs held around 5-6000rpm.. spray some water on the pipes (dont touch them, they'll be hot hot hot!) everyone should evaporate the water with a nice fizzing sound.

I know you tested them for a spark but have you actually swapped front / rear coils yet just to isolate? I don't think it will make any difference but worth trying to remove one more thing.

Neosophist wrote:The easiest way to see if the rear carbs have fuel is to unscrew the drainscrew on the carb (can do it with them on)

if fuel comes out its getting fuel.

Have you connected vaccum balance gauges to the engine?

If the carbs arn't balanced properly the pipes will warm up at different temps.

(can test for this besides the bike idling rough) warm the bike up with the revs held around 5-6000rpm.. spray some water on the pipes (dont touch them, they'll be hot hot hot!) everyone should evaporate the water with a nice fizzing sound.

I know you tested them for a spark but have you actually swapped front / rear coils yet just to isolate? I don't think it will make any difference but worth trying to remove one more thing.

I'll check the carbs for fuel, they were full when I drained them having taken them off yesterday so expect they'll be OK this time too.

I haven't vacuum balanced them, did the drill bit method but the fronts get very hot very quickly, the rears are cold to the touch, barely warming while the fronts are roasting

I have swapped coils and plugs and leads, I'm getting sparks from the rear leads, I put a screwdriver in the lead, and got it to arc to the frame, both rear leads are doing this. The plugs from the rear cylinders are now in the fronts and they're running, the plugs that were in the front are now in the rear and they're not.

The engine note doesn't change at all with the rear HT leads removed from the plugs

If I leave the rear HT leads and one of either the front leads it won't start at all

I appear to have a twin cylinder motorcyle of 200cc

edit: Just loosened the drainscrews, ther's fuell in there, so is it getting to the cylinders?

Compression test might be worth doing

Drunkn Munky wrote:Compression test might be worth doing

Done a few weeks ago, all good, I can't see it'd lose the head in less than 100 miles

OGS,

I have looked at your old posts, but can you say,
Was the bike in use or left standing. [how long]

Can you confirm that,

The 2 rear cylinders hardly work.
They both have a good spark.
The float bowls are full.
The ex pipes run cool.

Sounds like usual pilot circuit carb fault, but need confirmation.

Dave. OWS

arsey30 wrote:OGS,

I have looked at your old posts, but can you say,
Was the bike in use or left standing. [how long]

Can you confirm that,

The 2 rear cylinders hardly work.
They both have a good spark.
The float bowls are full.
The ex pipes run cool.

Sounds like usual pilot circuit carb fault, but need confirmation.

Dave. OWS

Dave

Thanks, a bit of history:

The Bike was standing for about a year before I got it, it ran enough for the seller to get to the MOT test station and then for me to get it home (20 miles), then I ran it for about another 50 miles or so before the reg/rec failed, changed that and the battery, then it staretd suffering fuel problems, cutting out at idle and I noticed it was smoking a bit (condensation). So thats when I started the oil change, coolant change, valve clearances, carb strip down etc etc and things have slowly spiralled downhill since! Its been working a bit then failing and so on.

Currently yes the two rear cylinders hardly work, at least I assume they don't as removing the HT leads makes no differennce to engine note or running

The spark from the plugs seems OK, orange rather than blue from what I can see, but the plugs from the rear work OK in the front and I have changed the coils over, the one at the front now was at the rear yesterday. I also used the rear HT leads on the front and they worked OK there too, I have since put them back but the plugs and coil at the front now were at the rear yesterday.

The float bowls are full, I assume they are anyway, I loosened the drain screw a bit earlier and fuel came out. when I took the carbs off the other day and drained them it semed the same amount came out of each one.

Tne rear pipes are running very cool indeed, the fronts get too hot to touch within a minute the rears are barely warm after 5.

I hope it is the "usual pilot circuit carb fault" whatever that is?

As always your advice/suggestions more than welcome

Ta

Do the rear ex get hot at all, i.e at high revs.
I am not far from you, e mail or pm me if you want me to have a look and listen, I can take your carbs home to clean them.

Dave.

arsey30 wrote:Do the rear ex get hot at all, i.e at high revs.
I am not far from you, e mail or pm me if you want me to have a look and listen, I can take your carbs home to clean them.

Dave.

Haven't really tried at high revs, I will do that later this morning.

I'll try that and let you know, thanks for the offer of a look and listen etc.

Cheers

Best clean the carbs before refitting, did you blow them clear with an air line and remove pilot screws, jets, tops.
Dave.