GPR\XLT Carb Upgrade\ Accelerator pump removal

[Oleg Russia]

Update. works very well. the color of the candles is brown.

1200R Aftermarket F/A's (Flame Arrestors) chokes intact

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

[Glenn240]

I have a 2000 GP1200R that lost power late last season. Based on the symptoms of my problem, it really sounds like I have bad reeds. Since I will have to remove the carbs to get to them anyway, I figured it would be a good time to rebuild them. While I'm at it, I decided to do a few upgrades. I'm planning to spend this weekend getting it running again, and have questions.

Right now I have a D-Plate installed and have bypassed the oil pump. It was running great, but I would like to coax a little more power out of it. To that end, I have ordered Riva Flame Arrestors and carbon reeds. I'm also putting in a Solas Impeller and a Primer kit, but that's not part of the questions i have.

Basically, I want to know if I should remove the Accelerator Pump as specified early in this thread, and if I do, should I install new jets? It may sound like a silly question in the context of the original post, but that post is about the 66V engine and after checking, my ski has the 67X. I've looked for information regarding the differences in the engines and if they were different in their factory setup but can't really find it. So I'm asking here.

New jets and needles will set me back around $75, with another $100 for EZ-Tune screws and $50 for cover plates. But it's not the money that I'm concerned about, I've never messed with jets before and am worried that I won't do it properly.

Most of the time when I'm riding I'm going balls-out or I'm idling. What are my likely consequences if I just leave that to another day and stick with the Accelerator Pump and OEM Jetting? If I do remove it and replace the jets (assuming I do it properly), will I get a noticeable performance improvement?

I've read this entire thread a couple of times, and there's a lot of good info in it. Just asking for clarity here.

Just saying that your ski has "lost power" is a bit vague, and therefore assuming that you have bad reeds is not exactly the most scientific way to regain "lost power" in my opinion. Have you pulled the spark plugs to inspect them or better yet done a compression test?? Those are the first two things I would do, and they are free, before you go spending money and throwing parts at it. If the compression readings are good, then I would start trying to diagnose what caused the power loss. BTW the 66V and 67X engines are basically the same, both 1200PV engines, just different stampings on the respective cylinder heads.

Doing carb rebuilds is certainly a good idea, especially if it has never been done, or if you don't know when it was done last. Get OEM kits, don't waste your money on aftermarket kits. Regarding re-jetting, that is pretty much a must when you are making a change somewhere else. The Riva flame arrestors will flow more more air, so you will need more fuel. Given that the whole reason for this thread was to address the inherently lean conditions with the stock setup, changing reeds or flame arrestors without re-jetting is a recipe for disaster IMHO. Carbon reeds themselves are not going to make any real difference in overall power, but will they will likely offer a little better throttle response, at least until they fatigue over time and no longer seal well. I wouldn't waste your money on carbon reeds on an otherwise stock engine. Stock reeds will be fine for your application, and offer better long term service life.

If you are not 100% confident in what you are doing with the carbs I would strongly suggest you find someone that can do it for you. A mistake in rebuilding and/or carb jetting can easily result in a seizure or worse, especially if you are running "balls out" as you stated. Just my 2 cents here, take it for what it's worth.

[Jonesyfxr]

Remove the acc pump. just remove the acc pump wheel and block off the line, use the oil injection lines for the primer lines. We did this mod and have our ski dialed in.

[Bellington]

I have a 2000 GP1200R that lost power late last season. Based on the symptoms of my problem, it really sounds like I have bad reeds. Since I will have to remove the carbs to get to them anyway, I figured it would be a good time to rebuild them. While I'm at it, I decided to do a few upgrades. I'm planning to spend this weekend getting it running again, and have questions.

Right now I have a D-Plate installed and have bypassed the oil pump. It was running great, but I would like to coax a little more power out of it. To that end, I have ordered Riva Flame Arrestors and carbon reeds. I'm also putting in a Solas Impeller and a Primer kit, but that's not part of the questions i have.

Basically, I want to know if I should remove the Accelerator Pump as specified early in this thread, and if I do, should I install new jets? It may sound like a silly question in the context of the original post, but that post is about the 66V engine and after checking, my ski has the 67X. I've looked for information regarding the differences in the engines and if they were different in their factory setup but can't really find it. So I'm asking here.

New jets and needles will set me back around $75, with another $100 for EZ-Tune screws and $50 for cover plates. But it's not the money that I'm concerned about, I've never messed with jets before and am worried that I won't do it properly.

Most of the time when I'm riding I'm going balls-out or I'm idling. What are my likely consequences if I just leave that to another day and stick with the Accelerator Pump and OEM Jetting? If I do remove it and replace the jets (assuming I do it properly), will I get a noticeable performance improvement?

I've read this entire thread a couple of times, and there's a lot of good info in it. Just asking for clarity here.

[vinnied]

Idle should be set in the water and under load. This will result in a higher idle on the trailer but is ok

Yeah that makes sense I guess I'll try resetting the lows to 1 turn out and set the idle in the water to see what it does. I have to get the carbs out anyways because the throttle shafts are locking up unfortunately.

[Jonesyfxr]

Thanks for the responses I looked into the piston wash and also tore the carbs down to rebuild again I also re synced the throttle plates. Now all of the plugs are evenly wet. I took it out on the water today. The highs are great but at lower rpm it likes to pop and the transition between low and high jet is pretty instant. I did turn the lows down about an 1/8 to a 1/4 because I couldn't get it to idle out of the water very well with out doing that.

Idle should be set in the water and under load. This will result in a higher idle on the trailer but is ok

[vinnied]

Getting better.

I have this same problem. Any chance you're still on this site and figured out the issue?

Thanks for the responses I looked into the piston wash and also tore the carbs down to rebuild again I also re synced the throttle plates. Now all of the plugs are evenly wet. I took it out on the water today. The highs are great but at lower rpm it likes to pop and the transition between low and high jet is pretty instant. I did turn the lows down about an 1/8 to a 1/4 because I couldn't get it to idle out of the water very well with out doing that.

[Hydrotoys]

Wet or Dry plugs mean nothing in 2stroke tuning. Research piston wash.

[Jonesyfxr]

I have this same problem. Any chance you're still on this site and figured out the issue?

Check the fuel line and carb for restrictions

There has to be a blockage somewhere on that carb.

[vinnied]

Same problem

Firt time poster, used greenhulk a lot while rebuilding my engines. I have two xlt 1200 from 2001, living in the Netherland. Rebuilded the carbs and used osidebill resipe:

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.

Just finsihd the first test ride, low RPM's pretty good throttle response. Max RPM goes to 6000 not to 7 before oside bills reciepe, really missing power and speed. Not very response on the throttle.

cylinder 1 wet plug (fuel)
cylinder 2 wet plug (fuel(
Cylinder 3 dry plug like supposed to

Can anyone please send me in the right direction? Have quite a lot experience with maintaining my ski's. Dont want to search hours if somebody knows where to look for.

Many thanks!

I have this same problem. Any chance you're still on this site and figured out the issue?

[Jonesyfxr]

Hi all.

New to this group and trying to wrap my head around the need for a cat or D-plate.
My question is - if you remove the catalytic from gp1200r or gp1300r, do you really need to replace with a D-plate ? can you just use the delete chic? what exactly does the D-plate do apart from create exhaust restriction / backpressure ?
Does it aid in the expansion chamber soundwave effect that 2strokes need in order to create more power ?
I'm saying this as I always thought the exhaust being submereged created enough necessary backpressure/restriction.
I previously had a rebuilt gp800r which had neither a cat nor a D-plate but still managed 80kph. reuilt carbs also worked great.
Thanks in advance

The D plate was developed to create some back pressure.... without it the ski is a dog.

[ouzo]

cat removal gp1200r and gp1300r

If you replace the cat with a d-plate is it recommended to remove the accelerator pump and also to rejet the carbs?

Hi all.

New to this group and trying to wrap my head around the need for a cat or D-plate.
My question is - if you remove the catalytic from gp1200r or gp1300r, do you really need to replace with a D-plate ? can you just use the delete chic? what exactly does the D-plate do apart from create exhaust restriction / backpressure ?
Does it aid in the expansion chamber soundwave effect that 2strokes need in order to create more power ?
I'm saying this as I always thought the exhaust being submereged created enough necessary backpressure/restriction.
I previously had a rebuilt gp800r which had neither a cat nor a D-plate but still managed 80kph. reuilt carbs also worked great.
Thanks in advance

[jetskiaz]

OKAY experts out there!!!

2001 Yamaha XR1800 2 fully rebuilt STD size motors

Air fuel separator with electric fuel pump being used to prevent air into carbs

Can i use OSIDE recipe for the carbs on this boat with return mod?

Can i just use his jetting and popoff specs that are tried on true or will the BOAT need different settings due to size and weight?

Anyone have a perfectly setup XR1800 thats wants to share their perfect reliable setup?

thanks in advance,
Chris in Arizona.

[Pilotoat]

You have the ever so popular mid range seizure. This is due to the lean stock carb settings. Go to the 2 stroke section and look at Oside Bills recipe or “Carb settings I have used”

Lots of knowledge here.. you’ll get through it

Thank you will take a look. The issue is I keep finding the recipe for a combination with aftermarket Flame Arrestor, and I have the standard airbox.

Will keep looking.

[Jonesyfxr]

You have the ever so popular mid range seizure. This is due to the lean stock carb settings. Go to the 2 stroke section and look at Oside Bills recipe or “Carb settings I have used”

Lots of knowledge here.. you’ll get through it