Triumphrat

guzzi · 03-06-2006, 09:01 PM

I took off the carbs, found the main jets and pilot jets to be not plugged. No nasty gas smell, or smeg. Put in new plugs, put in allen screws in carb, checked the diaphram, no apparent holes. Air hole not plugged in slide. Not sure how to clean the starter jets, but running a piece of safety wire up in there didn't allow it to go very far on either side.

Adjusted the idle screws to 2 3/4 turns, per instructions.
Ran vacuum balance hoses between both the carbs and the intake manifolds vacuum ports.

removed/ inspected air filter, no obstructions, no vacuum leaks.

Bike still runs on one cyl (l/h) with choke out, then after a little while, it picks up the r/h cyl intermittently. Runs like stink when it "catches"

Plug wire ends going into coil are shiney, not corroded. I did NOT run a resistance test on them yet.

Lh plug chocolate brown rh was black, not tooo sooty.

Any ideas? The bike runs better with choke out, but still intermittent. Spooky....

Shorty · 03-07-2006, 01:43 PM

Guzzi (shorty)...I had a similar problem where one of the cylinders (the right side) hesitated on start-up, but within a few seconds ran ok and didn't give any more problems afterwards. I replaced the plugs twice in 6 months and the last set were the iridium type...no problems since then.
However, someone suggested that I check/disconnect some carburator wiring (if memory serves me right...the feedback potentiometer?...which I never did). Either way, I also have both of my carbs vacuum ports connected after I synchronized the carbs uysing a manometer...seems to run fine that way. I also believe in a little Marvel Mystery Oil in the gas tank.

Shorty

gm16sw · 03-07-2006, 02:20 PM

You guys should use a mercury gauge to balance the carbs. Are both of your ignition coils functuning properly? maybe one is bad or the connection to your ignition block is bad. Just so you know, I am pretty sure the bike will never ever completely stop backfiring, no matter how you tune it. I think it is a design issue in the carbs themselves. Probably the only way to eliminate the backfiring totally, is by replacing the carbs with a different brand or race carbs. But since you probably aren't planning on racing it, just get used to a little pop every now and then. Good luck.

03-07-2006, 02:57 PM

Have you checked spark to both plugs? Any metal in the oil? Compression test each cylinder?

dazco · 03-07-2006, 03:44 PM

I was goona mention plugs too, but get some iridiums. Aside from feeling a definate small but definatly worthwhile increase in mid power they also helped the starting and idle a bit too.

guzzi · 03-08-2006, 01:24 AM

I put new plugs in it. Same ole thing. Then I got a brainfade, and switched the spark plug wires. Duh. Now the LH cyl stumbles, and the RH runs better. Funny, they both metered out identical to about 5k ohms So, I am gonna make up a new plug wire tomorrow. Bought a new pair of NGK 5k ohm plug ends identical to the stockers, and have some new stranded ignition wire. If that don't solve the problem, we'll try a new coil/wires from one of the online outfitters.

Gonna order a UNI filter, and some new 125 and 42 jets while I'm at it. Still waiting to see if the SV650 oil drain plugs will fit in the AI holes. If they do, they're less than 2 bucks a piece, and we'll finish the AI job. I might be able to actually ride this thing next week.