T500 no start

[87m6chris]

1975 engine, drive train and electricals
Hi guys,
just got the bike back together after a winter of restoration.
I didn't expect it to fire up on the first kick but after several hundred kicks I'm pulling my hair out. The crank seals are new, both barrels and pistons/rings looked good so I left them as is.
New gaskets for the entire engine, rebuilt carbs, new rubber on either side of the carbs, freshly lined gas tank, new lines with fiters, new ignition coils, spark plugs(good fat spark) new air filter. New points and coils, pretty sure the timing is right, all electrical connection were cleaned.
For every 10 kicks or so I get maybe 1 hit which is more like a puff but it never catches.
In desperation I pulled the air filter and gave it a quick shot of ether (Quick Start) but that made no difference.
Can anyone suggest a starting point?
Thanks,
Chris

[tz375]

I'd start with timing. You might want to double check that the spark occurs at more or less teh right time. You can take out a plug and lay it in teh HT lead against to motor and turn the motor over slowly and watch/listen for the crack and see that it's more or less spot on.

Or use a test lamp or a buzzer.

Are the plugs wet or dry? By now they should be pretty wet.

[titan performance]

I'm with TZ......I think it's most likely ignition timing. The fact that you are getting some combustion would imply the fuel is getting there.

Just a thought, but this has happened many times before....check you have the carb slides in the right way round !!

[rbond]

Also check that the left points are firing on the left plug, not the right......

[87m6chris]

Thanks, I'll start there. While doing some investigating today I realized my brand new petcock keeps flowing fuel in the off position into the right carb so it's over flowing and the left carbs float bowl is dry even though the fuel line is full, so some things to sort out first then back to the timing.

[87m6chris]

Some progress today, sorted out the petcock, sorted out the dry fuel bowl, re-timed and re-gaped, then I realized that I had the spark plug leads reversed, what a twit.
When I kick it over now I get 3-4 hits then it dies, the plugs are wet, I have the fuel enrichment
on (choke), battery is new and fully charged and the air temp. is about 40*F the bike might be a bit colder. I's almost starting, not sure what else to check.

[650hardtail]

try a new set of plugs and less choke

[rbond]

There is a possibility that there is still a lot of fuel in the crankcase from previous attempts to start it. Try no choke, no throttle. If it hits, do the 'two stroke twist' with the throttle to try to get it to speed up (2 or 3k rpm) enough to clear the excess out and run cleaner. You may have to put partial choke on then 'til it warms up. If still no joy, then re-visit the timing, then check fuel flow again from the petcock, finally pull the carbs back down and triple check jetneedle position, float level (check for fuel in floats) pilot screw adjustment. I know you have done all this, sometimes you just have to do it 2, or 3 times before you catch a mistake, overlooked something, or you just didn't hold your mouth right when kicking.
If it STILL won't start, get out your bicycle(so you can ride on two wheels) and a 'for sale' sign. Or if so inclined pull out your gun and lots of ammo, it's going to 'fire up' somehow!!!!

[jabcb]

Did you try bump starting it? Usually works for me on a T250/T350 that almost kick starts. After you get it running & cleared out the crankcase, then you can dial things in so it kick starts.

Just be careful about it and be prepared to deal with an over-reving engine if it happens. Also worth remembering that if it doesn't start going down a hill, you'll have to push it back up the hill.

[tz375]

Some progress today, sorted out the petcock, sorted out the dry fuel bowl, re-timed and re-gaped, then I realized that I had the spark plug leads reversed, what a twit.
When I kick it over now I get 3-4 hits then it dies, the plugs are wet, I have the fuel enrichment
on (choke), battery is new and fully charged and the air temp. is about 40*F the bike might be a bit colder. I's almost starting, not sure what else to check.

Plugs are wet, crankcases have some fuel in them.

Fuel OFF
Choke OFF
Ignition ON
Throttle Wide Open

Lick it till it fires up and only then release the throttle. What you need is more air and no more fuel until it burns off the excess. Throttle wide open means gas velocity is low and it has very low vacuum so it draws in little or no fuel until it really gets firing fast, so it clears its lungs out.

If that is still a bust, take the plugs out and push it in gear to blow surplus fuel out of the plug holes. Then fit clean dry plugs and try again.

[Suzsmokeyallan]

These really vague comments posted, worry me about you three.

rbond

Or if so inclined pull out your gun and lots of ammo

Such violence around an innocent old bike, you'll surely give it a starting complex.

jacbc

Also worth remembering that if it doesn't start going down a hill, you'll have to push it back up the hill.

Hey can I get one of those double sided hills, this single sided one is working me too hard.

tz375

Lick it till it fires up and only then release the throttle

Where on the bike is he to 'lick it', with his tongue I'm supposing here, that sounds slightly kinky to me.

Chris watch these guys carefully, they have plans for your bike.

[87m6chris]

GOT HER GOING! (cough cough choke can't breath) Clouds of smoke, too much assembly lube I guess.
After my defeat on Tuesday I pulled the plugs and let it sit for a couple days and to think through the excellent advice you guys gave me. Put them back in just now and she started on the first kick. Now I can't get her to settle down to idle, I have to keep the revs up at 3000 rpm to keep it from dying. RPM is fluctuating even though I'm not turning the throttle.
The spark plugs are NGK B7HS, the pilot air screws are at 1 1/4 turns out, the throttle stop screws are 3 turns out, the jet needles and 150 main jets are new but I still have the original jet needles and 97.5 main jets that are in good shape if I need them. Floats are set at 27mm,
there seems to be more smoke and steam coming from the right exhaust than the left but the crank was rebuilt with new seals so I don't understand that one.
I let it run at about 3000-4000 rpm for 5-6min. to burn off the extra fuel from the last starting attempt but couldn't get it to settle below 3000.

[87m6chris]

Started the bike up again after my last post and noticed alot exhaust smoke coming out between the header and the muffler, I forgot to install the new seals. So I did that and now she is idling nicely.
Still smoking too much but I still have to tweak the pilot air screws but the revs are down to 1500 rpm and it sounds great.
Thanks for all the help guys. I took some pics but I'll post them in a new thread.
Chris

[650hardtail]

a lil patience and advice...and you are on your way...congrats

[titan performance]

Chris.....a couple of posts back, are you saying you have replaced the 97.5 main jets with 150s?
Is the motor and air cleaner set up stock?