Help! 1992 TZR250 3XV Japanese domestic Carburetor basics, staggered Jets.

[mellorp]

Leave the on off tap in place. It's probably an RGV tap (straight fit). It's impossible to run the carbs dry with the vacuum tap (unless you fiddle with the vacuum pipe). With pump fuel being so full of additives it's very important to drain the carbs to stop the fuel attacking the carb internals when the engine is stood unused.

[Steveog]

Phil is right about the fuel tap. I put an RGV tap on mine thanks to his advice. Also, the stock vacuum fuel tap makes removing the tank a bit of a mess. As Warwick mentioned, be sure to cap off that vacuum outlet on the upper (left hand) carb.

The gentlemen that have responded to your questions are among the best of the best. I'm not including myself in their level of expertise. Not even close.

Good luck on first starting attempt. Use the choke and don't touch the throttle. It should "chuff" by the 5th or 6th kick....then fire in a few more kicks.
If not, start checking normal stuff. Fuel flow, spark, kill switch in the "on" position, etc. Once it starts, let it run a few seconds before trying to feed the throttle. Be ready for odd problems such as leaks.

I'd leave the air boxes off and use a satellite fuel feed for the first start. That way, you'll have a good visual reference of your engine bay and can react more quickly if something needs attention.

Steve 

[TZR250SMOKER]

SHES ALIVE!! Video of start up below.  Thank you to all you guys!  I will do that with the tap, I just ordered a few new gaskets for it and will leave the gravity fed one on.  I see your point about being able to drain the carbs so they don't gunk up like they were.. 

She fired right up and of course I forgot the vac caps for about 60 seconds.. duh! Mental check list failed me but got them on and she started idling decent.  I took her for a small rip and she GOES!! Yikes, get the leather on...  Someone put some nice Bembros on the front and she stops like you hit a wall.

Thanks again, if anyone else needs help, hit me up, I'll do my best to share what I learned.

https://www.youtube.com/watch?v=ryyE4euSQ2Y

[Steveog]

Congratulations. Well done.

[ybk]

Nice result!

It looks like you also still have the carb heating circuit attached (The 2 pipes that attached to the top of the carbs at 90 degree angles connecting the carbs, thermostat and lower cylinder together). You can blank those off on the lower cylinder and on the thermostat with rubber caps (same as on top cylinder) then remove the pipes. Makes removing and working on the carbs much easier, ie, no coolant spilling all over..

[TZR250SMOKER]

Ok Ybk, thanks.  I was cursing those hoses when I was removing them and reinstalling... So your saying carb heating does not matter, won't negatively effect performance?  Is that because its Florida, fair weather riding only?  I did notice the gunk in those fittings was odd, one nipple was oxidized away slightly, I thought they were vac hoses.  Your saying the coolant from the radiator comes down into that loop?  I did not get any coolant spill, better check my radiator but I did notice my reservoir was full.  Thank you.

[41juergen]

You better connect the lower cylinder with a small hose to the thermostat housing (where the stock hose get's in). With that you prevent air bubbles in the lower cylinder and you have the required bypass at "cold" start and the thermostat is still closed. In the thermostat there is only a very tiny hole as a bypass, it potentially can create a high pressure in the system until the thermostat opens.
just my 2 cents... 

[TZR250SMOKER]

Thank you, amazing how folks figure this stuff out! I will leave it stock for now.  Do I need to worry about purging the air out thru the radiator to ensure the system has no air trapped?

[41juergen]

If you have the whole cooling system as stock, I would think it "cleans out" by itself, no worries...

[mellorp]

Thank you, amazing how folks figure this stuff out! I will leave it stock for now.  Do I need to worry about purging the air out thru the radiator to ensure the system has no air trapped?

Everyone learns by mistakes. We've all made plenty (and continue to do so). The thing with the forum is people own up and share the knowledge. Unlike the 2T tuning guys of the 70's and 80's that would blow things up but only crack on about the good stuff......

[RockyFranco]

Hi

did anybody know where are those big differences coming from between model V1 and V4 ?

I mean V1 mit PJ 60/50 and V4 mit PJ 40/0
Or in general, why lots of model didnt use the powerjet for the front (right) cylinder ?
Does this differences really coming from the needle shape and atomizer dimension differences ?
If those components are equal left/right the front cylinder has no PJ only the rear.
If I bear in mind that more heat bad thermal conditiions for the rear cylinder, thise one should be the cylinder with more fuel...
I mean i total at full throttle for a 3XV1 the main jet size grade are 190+60=250 rear and 260+50=310 front


I'm glad to hear from anybody knowing this or from history

Thanks