Right, I'm having trouble in starting my 4/6 up after around 6 months in the garage. I drained the carbs before I put it away and cleaned them a couple of days ago. The fuel is fresh.

Can someone explain the nature of the 3TJ CDI restriction to me please? I'm trying to get the bike to start using 600 coils on a 3TJ loom with a standard 3TJ cdi (I want to keep the road niceties such as reserve and lights and stuff) I don't need to be told to use the 600 loom and 600 cdi please. My thinking being that as the 3TJ cdi restricts revs to 12500 rpm if the speedo wiring is unplugged, it'd be ok to use on a 600 engine.

When the tank is full is the fuel switch normally open or closed, ie do I need to short the reserve switch out to get it to fire on all four?

I don't need to be told to try the 600 loom and cdi, thanks

You could try the .... oh no wait.

Ok
If the CDI doesn't recieve the 0kmh signal it restricts to 12,500rpm in all gears - your thinking should be ok on this.
The reserve is activated by the sender in the tank. The sender tells the CDI and the CDI cuts 2 cylinders until you flick the switch. You could wire the sender circuit open or closed and junk the sender and reserve switch completely.

Now - if the bike ran before it should run now, unless you changed something. It could be there's not enough fuel for it to be off reserve or it could be in the area where the CDI cutting the 2 cylinders. Add some more fuel.
Check the sparks - it could be on two.
Try running it on carb cleaner.

Evilchicken0 wrote:You could try the .... oh no wait.

Ok
If the CDI doesn't recieve the 0kmh signal it restricts to 12,500rpm in all gears - your thinking should be ok on this.
The reserve is activated by the sender in the tank. The sender tells the CDI and the CDI cuts 2 cylinders until you flick the switch. You could wire the sender circuit open or closed and junk the sender and reserve switch completely.

Now - if the bike ran before it should run now, unless you changed something. It could be there's not enough fuel for it to be off reserve or it could be in the area where the CDI cutting the 2 cylinders. Add some more fuel.
Check the sparks - it could be on two.
Try running it on carb cleaner.

I knew it'd be you!

Thanks for the help EC.

im starting to think evilchicken is........."Mr Yamaha!!!""...lol

I wouldn't want to dissapoint anybody would I

Does it run yet ????

Evilchicken0 wrote:I wouldn't want to dissapoint anybody would I

Does it run yet ????

It's trying to, it sounds like it's chugging away on two on the starter then just dies. Meh.

the speed or rpm restriction is as the evil one said

but that doesn't sound like your problem,
because it should still start, even when restricted to 12,000rpm
have you checked the starter relay (the 1 by the fuse box, has about 12 wires connecting to it) as this controls the reserve system as well as the clutch, side stand, neutral, kill, and reserve switches and unless all the switches are in the correct order, ) then it wont normally turn over
BUT
from experience mine would turn over, but not take, unless i squirted petrol down the pump to carb pipe,
so after a load of head scratching,
i figured it was the relay, (cos the pump worked when i put 12V across it, but not when connected to the loom)
when checked the relay had a corroded/broken off connector, so the pump got no signal and the carbs got no pressure from the pump so it would only fart and pop, and if it did take, it would only rev to about 4K then die back to farting and popping, cos the carbs weren't pressurized

just a thought

Hogdigerdy Dog wrote:the speed or rpm restriction is as the evil one said

but that doesn't sound like your problem,
because it should still start, even when restricted to 12,000rpm
have you checked the starter relay (the 1 by the fuse box, has about 12 wires connecting to it) as this controls the reserve system as well as the clutch, side stand, neutral, kill, and reserve switches and unless all the switches are in the correct order, ) then it wont normally turn over
BUT
from experience mine would turn over, but not take, unless i squirted petrol down the pump to carb pipe,
so after a load of head scratching,
i figured it was the relay, (cos the pump worked when i put 12V across it, but not when connected to the loom)
when checked the relay had a corroded/broken off connector, so the pump got no signal and the carbs got no pressure from the pump so it would only fart and pop, and if it did take, it would only rev to about 4K then die back to farting and popping, cos the carbs weren't pressurized

just a thought

Now there's an idea, thanks for that The pump does do its clicking thing and there was fuel in the float bowls when I took the carbs off but I do have a couple of spare looms I can try. I hate multis when they go wrong The thing is, the loom was working ok on the 400 engine that it was on so I can't understand why it won't start up now. I think I'm going to put a 400 engine back in it, at least I know that engine does run with this loom!

You could try a 600 loom and CDI

not suggesting it's the fuel pump with yours, (probably not) that was just my experience
but the relay controls the reserve system as well, which will cut the engine to 2 cylinders,
so if you've got a spare loom with the relay, then i'd change the relay first, rather than the loom,