It followed me home!!

concours said:
I keep a spare on hand, I'll check it. Maybe it needs vacuum to seal?
I'll pull on it with the Mityvac
Click to expand...
You maybe right about a vacuum
I can't see how it could possibly close off without a seal on the end of the piston blocking the port in the closed position
 
Well the primer idea didn't work
I tee'd the feed pipe to the primer into one of the fuel pipes
And it the fuel ran straight through the primer pump into the carbs and out of the inlet
I tried giving it a pump but it made no difference
I tried holding the pump above the fuel tank and it made no difference
The fuel just just ran through the pump and out of the carbs
So it definitely needs some sort of check valve or a dedicated feed that can be turned off?
 
baz said:
Well the primer idea didn't work
I tee'd the feed pipe to the primer into one of the fuel pipes
And it the fuel ran straight through the primer pump into the carbs and out of the inlet
I tried giving it a pump but it made no difference
I tried holding the pump above the fuel tank and it made no difference
The fuel just just ran through the pump and out of the carbs
So it definitely needs some sort of check valve or a dedicated feed that can be turned off?
Click to expand...
Dammit!!!

You got a duff one.
I was mistaken when I said Taiwan. The one I had in stock is US made.
It followed me home!!
 
  • Like
Reactions: baz
baz said:
I take it yours has a one way valve built in? IE the fuel can't just run through it
Click to expand...
Yes. Please don't give up. Have the seller send a new one. Also, do not dry cycle the primer, it will make plunger seal peal out of it's groove.
 
concours said:
Yes. Please don't give up. Have the seller send a new one. Also, do not dry cycle the primer, it will make plunger seal peal out of it's groove.
Click to expand...
Just to be sure we are talking about the same thing
Whereabouts on the primer is the one way valve?
It's probably me but I can't see where there could be one?
Cheers
 
concours said:
I can disassemble one later.
Click to expand...
Only if you have time
You seem pretty busy with other things
But thank you very much if you do
It's probably me not understanding how this is supposed to work
There doesn't look like enough room for a valve there to me
And I was thinking the petrol tank on jetski maybe lower than the carburettors
And are fitted with a fuel pump ?
The petrol tank on this bike has 4 fuel tap bosses
I'm going to fit another fuel tap that will tee into the carbs
Then open the tap for a few seconds until it floods the 3 carbs as you would with Amal tickler buttons
See how that works out
I'm also changing from 15 to 25 pilot jets with some 30s on order
 
baz said:
Only if you have time
You seem pretty busy with other things
But thank you very much if you do
It's probably me not understanding how this is supposed to work
There doesn't look like enough room for a valve there to me
And I was thinking the petrol tank on jetski maybe lower than the carburettors
And are fitted with a fuel pump ?
The petrol tank on this bike has 4 fuel tap bosses
I'm going to fit another fuel tap that will tee into the carbs
Then open the tap for a few seconds until it floods the 3 carbs as you would with Amal tickler buttons
See how that works out
I'm also changing from 15 to 25 pilot jets with some 30s on order
Click to expand...
Typically installed UP stream, between the tank & pump, gravity feed, 8-10" head (tank above carbs)
100% sure you have a bad primer.

The one kick cold starts will make this exercise worthwhile.
 
  • Thumbs Up
Reactions: baz
concours said:
Typically installed UP stream, between the tank & pump, gravity feed, 8-10" head (tank above carbs)
100% sure you have a bad primer.

The one kick cold starts will make this exercise worthwhile.
Click to expand...
You were 100% correct
Curiosity got the better of me
 

Attachments

  • It followed me home!!
    IMG_20240115_212440178.jpg
    279.6 KB · Views: 46
baz said:
Is there anything else that could cause one cylinder to only run on full choke? Maybe a massive air leak?
Click to expand...
Does your bike need "choke" when fully warm?
My hard to start racing Honda CB250 will only start with left cylinder enrichened. After about 4 minutes no enrichener needed.
When warm, AFR is measured good. Never managed to find out why.
The Venom which also has a Mikuni needs to be enriched when cold.
I think the three 2-stroke racers don't need to be enriched.
 
Mike40M said:
Does your bike need "choke" when fully warm?
My hard to start racing Honda CB250 will only start with left cylinder enrichened. After about 4 minutes no enrichener needed.
When warm, AFR is measured good. Never managed to find out why.
The Venom which also has a Mikuni needs to be enriched when cold.
I think the three 2-stroke racers don't need to be enriched.
Click to expand...
No once warm it'll start fine no enrichment needed
Starting from cold I put all 3 levers full on and kick it several times throttle closed or open it makes no difference it won't fire
I then kick it with the chokes turned off and it'll fire but immediately stops unless I'm quick enough to turn at least two of the chokes on until it warms up
I did manage to start it the other day by only engaging the choke on the centre cylinder and then the two outer cylinders
My t160 that's also fitted with mikuni VMs behaves similar I engage all 3 chokes and spin it on the starter and it does nothing until I open the throttle
Then it fires right up
I have an Indian royal Enfield with an enrichment type choke
This too will not start with the choke on
I have to kick it over with the choke on and then turn the choke off and kick it with the throttle closed and it'll start and idle!!!
I'm starting to think it must be me?
Because none of them start with an enrichment jet engaged and the throttle closed like the book says
 
You must log in or register to reply here.
Back
Top