Suzuki 2 Strokes

Hello all, my 250 project is nearly complete and I've had it running several times along with a couple of short (2.5 mile) rides last weekend. Its still very much winter here but I was able to sneak it out when my road was dry; temp was about 35f (+2C). The bike runs very well, strong acceleration, nice even idle @ 1500rpm or so. I've got the fuel mixed, (1st tank) but the injection system is working fine, no bubbles in the lines and the tank level is dropping since first filling.
My only problem is cold starting. Enricher on, it takes ten kicks before she fires and runs. When she starts, she stays running and within a short time I can flick the enricher off and the bike will idle.
I've pulled the plugs after 4-5 kicks to check for flooding, but they are always dry at this point.
I've opened the float bowl drains before kicking and they are full.

I've been through the carbs several times now. I've paid very close attention to the enricher circuit. This bike runs only one enricher on the left carb, and then a hose that connects from there to the right carb venturi. I've never played with a twin carb enricher system like this; my GT500 had an enricher on each carb, linked, with a common lever.
I have the correct float bowl on the corresponding carb, (only one of them is crossed drilled to allow gas to enter the enricher chamber). I've confirmed that the pick up tube is clear and the plunger is lifting and opening the circuit. I've changed the short hose between carbs. I'm running an aftermarket manual petcock and have the vacuum nipple on the left carb, capped off.
I've gone to #40 pilot jets, (stock is 30's, my bike had 20's installed).
I can't see any signs of lean running --- I installed new outer crank seals. There is no rise in idle as she warms up. I haven't been able to do much of a spark plug read with limited running but so far they are somewhere around off-white, not quite tan. (hopefully in the next couple of weeks our weather will be good enough for me to run it further and get a better reading)
I've checked for an air leak using quick start, sprayed at the base gaskets, carb flange area etc with no affect.
Once running, if I apply the enricher the rpm rises slightly.

The odometer shows just over 10,000 miles but I have no history on the bike.

Sorry for the long post but I figure the more info I provide, perhaps someone might have an idea for me to try. Or maybe someone with the same bike can will tell me that these particular twin carb/single enricher set ups were hard cold starters? (in which case I'll live with it --- easy to kick over and it should only get better as the temps warm up)

thanks everyone!

Relic

By your plug description, it's running lean. Have you fitted an air filter in the housing and lightly oiled the foam?
Or expansion chambers?
Might be worth going one grade hotter on your plugs until the weather improves.
Keep the revs down a bit if you run hotter plugs.
Also check that the air filter is correctly fastened to the carbs without any leaks - try spraying a bit of carb cleaner or easy start around the air filter.
If the engine revs rise, there's your leak.

Alan H wrote:By your plug description, it's running lean. Have you fitted an air filter in the housing and lightly oiled the foam?
Or expansion chambers?
Might be worth going one grade hotter on your plugs until the weather improves.
Keep the revs down a bit if you run hotter plugs.
Also check that the air filter is correctly fastened to the carbs without any leaks - try spraying a bit of carb cleaner or easy start around the air filter.
If the engine revs rise, there's your leak.

Thanks Alan, yes I have the stock airbox with the paper element filter installed. I don't think there is a leak between the filter housing and the carbs as the boot is nice and soft, clamps tightened good. But next time its running I'll confirm there is no leak by spraying.
Stock exhaust as well with the original baffles.

Relic

Try the main needles with the clips one slot lower - so the needle is slightly higher and do another plug colour check.
The clip 'should' be in the centre notch, but....
I take it that the jets are correctly located in the carbs with good quality gaskets/O rings etc?
The fuel level should also be correct - I have an early (1972/3) original service manual that I scanned, which gives lots of settings for ALL models up to those years, including T250. If you want a copy, PM me your email address and I'll bung a copy in the 'post'.

Alan H wrote:Try the main needles with the clips one slot lower - so the needle is slightly higher and do another plug colour check.
The clip 'should' be in the centre notch, but....
I take it that the jets are correctly located in the carbs with good quality gaskets/O rings etc?
The fuel level should also be correct - I have an early (1972/3) original service manual that I scanned, which gives lots of settings for ALL models up to those years, including T250. If you want a copy, PM me your email address and I'll bung a copy in the 'post'.

I've been using the manual that Ian has posted on oldjapanesebikes.com but will pm you for your copy-maybe it has more info?
Float levels are correct for the info I have. I've gone richer on the pilots and the mains are larger than what shows in the manual I'm using.
It seems to me that jetting is very close and the only trouble I'm having is with cold starts. But as mentioned I haven't had a chance to really ride the bike far enough (in normal temps) to do a proper plug read. It was just above freezing when I did my only riding and that was just a very short 2 and a half mile run. The bike easily made 55mph in 5th, the only reason I backed off was because I was COLD. VERY COLD.

thanks again!

Interestingly, the later, 'ganged' carbs on the 380 and 550 have only two chokes, with the larger centre choke shared with the right carb via a joining tube.
I occasionally have some cold starting issues, but when so, always on the left cylinder, which has its own starter circuit.
All very odd!
Cheers,
Mike