GPR\XLT Carb Upgrade\ Accelerator pump removal

[speedysprocket]

I read a lot of this thread and didn’t find exactly what I was looking for.
Stock 2001 GPR and I plan to keep the accelerator pump, chokes, and stock air box. I can remove screens and drill holes in the box if I should, but ski also has the D plate. Which jetting and pop off setup should I go with? Mid range and top end felt ok, but bottom off idle has a terrible hesitation. I’ll be selling the ski, so just want it to right right, not necessarily fastest.

[1200Jet]

You stick with the stock jetting and pop off if your keeping the air box stock, do not modify the intake in this case.

Most people upgrade because the stock settings are tuned for emissions not performance. As a result of tuning for emissions these skis are prone to run very lean during midrange cruising. I'm sure you read about this in the previous pages.

The fix is to remove the stock intake and fuel pump and jet to the recipe.

[Adam]

so the single check valve is prone to leaking causing a stumble off idle when accelerating.....the double check valve prevents the leaking and cleans up the bottom end nicely

You are talking about the anti siphon valve ? And not the fuel pump check valves .

[speedysprocket]

So going to the D plate doesn’t affect jetting? You keep saying mid range will be lean, but stick with the stock jetting. Why?

[1200Jet]

So going to the D plate doesn’t affect jetting? You keep saying mid range will be lean, but stick with the stock jetting. Why?

Because no one has found a recipe that works with the stock intake. If you want to fix this issue you upgrade to flame arrestors.

[Just Jetski's]

anyone still using the recipe?

[Just Jetski's]

stock carb's, cleaned and completely rebuilt. Stock reeds, stock manifold.

Acc. Pump removed
chokes removed
carb restrictors drilled out 1/8"
95 main jet return
oil injection removed
fuel selector deleted
extended and clunked dual fuel pickup's
dual yamaha filter/seperator's
modified stock air box lower half, with stock screen and lid
front intake ducting removed

110 pilots
120 mains
95g springs
1.5 n/s _ 44psi pop off
95 return restrictor _ 1+ psi at idle

how long did this setup last for with the stock airbox?

[Crazypirate]

If using aftermarket flame arrestors use this reciepe with no accelerator pump..., if you using stock flame arrestor, use European setting on page 26 as posted by 3006phil. ..as a minimum, bump up pilots to Europe's 92.5 (on both 800pv and 1200pv,..95s are a hair rich) .... Lessons learned from experience, have run all those and I like the European best on mine.....But I'm not after topspeed, ...longevity, and good no wake load up is most important to me. (Aftermarket FA are too noisy for my taste)

[Oleg Russia]

Yamaha gp1200r 66v
Hello. Please, help. I bought used carburetors in Japan. He removed the stubs from the needles.
The high speed is 1 = 1.7\8 2 = 1.1\4 3 = 1.3\4
Low speed was calculated only on the first carburetor 1,1\4 on the rest I did not correctly twist and did not count


pilot jet 95 - 1 and 3 carb, 2 carb 135

main jet 140 all
pop off 30 psi
2.0 n/s
springs is like gold

What settings do I need to do?

[speedysprocket]

Finally got around to messing with it. The pop off springs in there had me over 70 psi. I put black springs in to get 52 psi across all three and it ran great. I’d recommend it for D plate and stock arrester with extra holes drilled.

[speedysprocket]

Well someone stole this GP out of my driveway on Christmas... It's probably being strippped down right now after all the time I put into making it run right.

[t0mpa]

Hi, we have just bought everything according to the recipie, 1200R Aftermarket F/A's (Flame Arrestors) chokes intact

• • 110 Pilot jets, 1 turn out on low speed adjusters
  • 120 main jets, 1-1/2 turn out on high speed adjusters
  • 1.5 Needle and Seat, 95 gram spring (Dull Silver) 42-45 avg. pop-off pressure.

We are planning on removing the accelerator pump and this is why i am posting.
I have the Mikuni cover plate, is there anything i need to know regarding this? I have never removed an accelerator pump before, is it really this simple?

1. Remove Accel pump and all tubing.
2. Install Mikuni cover plate (BN44/147 Cover, Stainless)
3. Cap all accelerator hose nipples

Nothing else i need to know?

Many thanks,
Thomas

[RMBC Freeride]

Finally got around to messing with it. The pop off springs in there had me over 70 psi. I put black springs in to get 52 psi across all three and it ran great. I'd recommend it for D plate and stock arrester with extra holes drilled.

@speedysprocket Sorry to bring up this old topic again, especially since your gp got stolen... but are you saying you used stock jetting but with black springs? Or did you use one of the other jetting combos on here?

I'm in the same boat: sold a gp that isn't running right. Has a d plate just want good jetting and no extra money spent on it and make it go away...
Thanks

[speedysprocket]

@speedysprocket Sorry to bring up this old topic again, especially since your gp got stolen... but are you saying you used stock jetting but with black springs? Or did you use one of the other jetting combos on here?

I'm in the same boat: sold a gp that isn't running right. Has a d plate just want good jetting and no extra money spent on it and make it go away...
Thanks

yes. Stock jets and softer springs to get 55 psi. I don’t remember the color. Probably whatever is softest since that seat is so tiny!

[srxr700]

yes. Stock jets and softer springs to get 55 psi. I don’t remember the color. Probably whatever is softest since that seat is so tiny!

Sorry to beat on this one..lol

So you ran..

N/S - 1.2
Black Springs - PO roughly 55psi
Stock Pilots - 87.5
Stock Mains -0 117.5
Stock Air box - Drilled for more flow