XL1200 Limited "missing" top speed?

[ChristerSG]

Hello!
I am fairly new to this forum. I bought my first PWC, a 2000 Waverunner XL1200 Limited, two weeks ago and have had a blast with it so far!
I have also been reading around this forum a couple of weeks and learned alot allready.

So far I have installed the D Plate with sensor chip. Waveeater clips and couplers are on their way.
I am also thinking of R&D Intake grate, Ride plate and pump seal kit. Since there is a short season here in Norway I will probably install this during the winter.
My goal is to try to get it to go around 62-63mph, with mostly bolt-on and easy installation parts. Or is this something that would be hard to achieve?

I do have one "problem" tho. Ive read that a stock XL1200 Limited should do 57-58mph @ ~7100 rpm or so, but my skis wont go faster than 53mph (confirmed with GPS), even after I changed the broken cat conv with the D Plate there was no change at all.
Since I dont have a external tach I am not 100% sure of my numbers, but here they are;
In the water 53mphs @ what seems to be around 6900 RPM (hard to read when driving). But on the trailer my rpm goes to ~7100.
Do you guys have any tips on where I should start to look?

Also, I am driving premix oil/fuel, since the last owner said that he used to do that as an insurance, but I am not sure if he did the oil block off mod, I will check that out very soon.

[brblommel]

sorry for the late reply but if you are running premix and dont have the oil pump blockoff then you will definitely loose 6-7mph. make sure that if you are premixing the oil pump is at least disconnected, ive heard of carbs running lean because they suck air through the empty oil lines. also, you bought the ski used... no matter what condition it is in pull the carbs, and either rebuild them yourself or have someone do it for you, also new spark plugs work wonders.

Goodluck and let me know how it goes!

[ChristerSG]

sorry for the late reply but if you are running premix and dont have the oil pump blockoff then you will definitely loose 6-7mph. make sure that if you are premixing the oil pump is at least disconnected, ive heard of carbs running lean because they suck air through the empty oil lines. also, you bought the ski used... no matter what condition it is in pull the carbs, and either rebuild them yourself or have someone do it for you, also new spark plugs work wonders.

Goodluck and let me know how it goes!

Thanks for your answer!

I changed the sparkplugs now, and that did not seem to help. As for the oilpump, the oil pump cable (the one on the "throttle wheel"? on the carb) is disconnected. Also, there is a half tank of oil, wich doesnt seem to have "moved" in the 3 hours i have been using it. I couldnt get a hold of caps for the oil lines, so they are still connected as normal.

How hard is it to rebuild the carbs? I have never done something like that, but if its not that hard I suppose I could give it a try.

Is there anything else that could cause this? The impeller doesnt seem to have to much of a gap to the housing either.

[kmc]

I think if the cable is removed, the pump goes to 'full on' and would pump oil and cause a lot of smoke, unless he also 'pinned' to to the minimum setting somehow. I wonder if the prior owner just pulled the pump off, took out the coupler, then put the pump back on. Then it wouldn't pump anything and you could leave all the hoses connected so you didn't have any leaks, and you would not need a blockoff plate either.

FYI.. if that tank is full of good oil, you could always get a syringe to draw oil out of there when you refill with gas to make your pre-mix. Then you know you always have some handy!

If you don't have history on the carbs, then definitely rebuild them. THere is a lot of detail on this site with everything you need. Look at the how-to's.

[ChristerSG]

I recieved my waveeater-clips and started installing them, but it seems the first valve doesnt have the pin. So I Guess I have to pull to top and check the cylinder. If the cylinder is undamaged, could I just order a new powervalve and slide it in there and attach it?

I suppose this would be the reason why it doesnt reach top speed. Unless the pin just fell out when I opened it up..

[Jnthn]

Factory top speed are tested with a 1/3 of a tank of fuel, if you have anything more than that i think thay you may be loosing top speed

[ChristerSG]

I reach 53mph even if the tank is almost empty.

Is it possible to install the SBT powervalve alongside the regular type?

[Jnthn]

Also i think that even the oil to fuel ratio may give you different top speeds. Mine is does something like 55mph, and it s got a solas impeller

[elmatta]

Riding over 1/3 tank only minimally affects the ski unless its at a full tank. Premix ratios do not give you better top speed. Premix + oil pump (which you should never do since its too much oil) does not affect the ski to loose 6-7mph. It would smoke a considerable amount then explode after the excess oil builds up in the cylinders. Clearance with impeller and wear ring is supposed to be very very small to not overspin the prop while it propels water behind it.

-Check compression
-rebuild carbs (isnt that hard if you have a manual)
-buy a block off kit (i dont think someone went out of their way in removing the pump just to remove the small plastic spinny thingy to then not have a block off kit.
-install PPK
-buy a tiny tach
-if/when you get a ride plate, angle it

[ChristerSG]

So, I replaced the broken powervalve and got a to 55mph for a very brief moment (with full tank). Was some chop, so maybe I get stable 55 on glass. Luckily the PV pin was stuck in the grease, so that saved me some work. Block off kit havent arrived yet, so nothing new there.