Thread: About XLL/XLT's
01-15-2007, 11:09 PM #1
While the XLL/XLT platform shares the same powerplant as the GPR, there are some mods that are specific to each platform. There are a lot of us that just aren’t satisfied with the stock performance of XL’s. As a general rule, any motor performance modifications that are discussed for the GPR is also applicable to the XL’s. I’m creating a how-to thread to discuss mods and issues for the XLL and XLT’s
A bit of history; the 1200 Powervalve (PV) motor that was such a success for the GPR starting in 2000 first appeared on the 1999 XL1200 Limited. The limited was produced in 1999 and 2000, then was replaced by the XLT1200 from 2001 to 2005. The differences in the two models are noted in this article in Boating Magazine:
“The 2001 XLT1200 is based on the 2000 WaveRunner XL1200 Limited. It retains the 2000's 155-hp, 1176cc triple-cylinder engine and top deck. A new silver cowl and recontoured seat update the styling. Running surface dimensions remain the same but have been slightly modified. The contour of the chines has been altered to improve tracking and stability at midrange speeds. The aluminum ride plate, which covers the pump assembly, is 3'11" longer and incorporates the contour of the inboard chines. This creates more flat surface. Both changes help the XLT1200 plane more quickly with a passenger aboard and feel more stable at midrange speed without sacrificing top end.”
While theses skis appear to simply be 3 seat versions of the GPR, they are in fact much different platforms. At 10’4” and 780 lbs, it’s almost 10” longer and over 130 lbs heavier than the GPR. This makes for a marked difference in handling between the two waverunners. The XL’s are sluggish compared to the lighter GPR’s; however, they can stay down on the water better in high speed off-shore conditions, maintaining higher speeds while the GPR’s are launching themselves skyward.
First and foremost; don’t consider doing any performance modifications to the XL platform without installing an aftermarket intake grate. When you suddenly cut the throttle off on modified XL, the weight shift from back to front drives the front hull chines into the water, causing the ski to sometimes turn sharply to the left at 60 mph. You will NOT be able to hang on, and the impact with the water (or other objects) will range from painful to traumatic. The most popular intake grate is the R&D or Riva (same product) scoop grate. It solves the turning problem, gives you better hook up in rough water, and a slight speed increase.
Another bolt on mod for the XL platform is an aftermarket ride plate. Once again the R&D/Riva is the popular choice. Off the shelf it will increase top end and come on plane quicker; modifications to the plates from Jim in Florida, Carl at Island Racing and others give an even greater increase in speed. These are the single most effective bolt-on way to increase speed.
Like the GPR, a pump plug kit and a new impeller can increase both bottom end power and top end speed. What works best for the GPR isn’t what works best for the XL’s, however. An out of the box Solas 12/18 works better for the XL’s than the 13/19 you would get for a GPR. Other custom bends from various impeller shops offer even more speed; what works best depends on the mods to the ski.
The 5 degree nozzle from the GPR will help top end; you can tap it out for a reverse bucket and have the best of both worlds.
All engine and exhaust mods for the GPR (Jetworks, D-plate, modified heads, ect.) are beneficial to the XL’s; these have all be covered at length on the forum here, and there is no sense rewriting it on this thread.
I’m calling out anyone else who has XLL/XLT specific modifications or known issues and fixes to post them here, to try to get all the information in one place. The XL’s are fun beasts to ride, and even more fun when we discover their true potential.
01-15-2007, 11:32 PM #2
I bought a 99 XLL when they first came out. People seem to have come a long way since then with them but that was the biggest most ill handling craft I ever owned.I had a Scat Trak pump in mine the ride-plate mod(at that time) flame arrestor,e.t.c... I raced that thing in the Long Beach to Catalina race and that thing beat me to death!!! I tip my hat to you for staying with it. I agree with your 60mph launch though... I got tossed a few times before I got used to it..
01-23-2007, 07:24 PM #3
The xll-xlt is not that hard to get speed out of like some people may think. The key to the xll-xlt to get speed is you have to get that big hull out of the water if you cant do that you will be fighting an up hill battle. I have devoted a whole year to the xll-xlt platform, I have been testing all kinds of different cut plates on the xll-xlt and finally found the one that will lift the hull up and still keep the ski's handling very good. To give you an example on some of the ski's i have done and what speeds are there. My special cut ride plate, R&D intake grate, All bolts filled, stock head milled, R&D dplate & chip, 05 pump on a 87mm or 85 mm nozzle depending if you want a better hole shot or top speed, carb. rejetting with flame arrestors. That will get you speeds from 66 mph. to high 67 mph. Not bad for a ski with no key way or advent and no reeds. Add them and now you are talking a ski that will run 68 to 69 mph. And then you have the extreme that i have were you change the pump shoe to a flat one and some other stuff that got me to high 72 to low 73 mph. on a 1200 non ported single pipe motor with stock carbs. I have sent my 1200 cylinders out to TJ going 1400 will keep you guys posted with results. If any one has any questions or about the products that will get you there can give me a call, Thank you, Jim
01-25-2007, 02:43 PM #4
- Join Date
- Nov 2006
- Miami, Florida, United States
Jim is right. Overall, it's just getting the hull out of the water. I can vouch for that. Referrence the hull? Great, great hull, I don't think it's a big hull at all. I think it's the perfect size, you have the ability for speed, you have a very sleek design with this craft, very comfortable ride & a great power plant. Look at the SeaDoos. Those things are huge. Compared to those skis, our XLT's are very mid-sized if you asked me
02-02-2007, 12:35 AM #5
- Join Date
- Mar 2006
Well all I can say is that my 2002 xlt (sea couch) is awesome!!!! I love it and thanx to Jim's advice it is almost hitting 70mph which by this summer that is where i plan to be.
02-02-2007, 01:47 AM #6
I have also noticed this past season that aftermarket sponsons made a BIG difference, not in speed but the walking side to side I had expierenced in the past with this hull. All the big names on here sell them if people are looking for a set. I have the Riva set but when held up againts the beach house not a tremendous difference in the two. I have heard of some guys modifying the Beach house ones with more whole positions for dialing in the hull.
02-03-2007, 07:45 AM #7
- Join Date
- Nov 2005
We have been building 70+ mph single pipe XLL / XLT's since back in early 2000.( this was before all the fancy go fast goodies of today) Much of the info already on this post is good info. Since then there have been a few new and improved performance parts to gain additional speeds. Ho pumps, new Rideplate mods (above and beyond the already fast old style modded plates ) bigger engines, REEDS etc.
There werent too many who "believed" in the performance of the XLL platform and were willing to take performance to the next level. I for one did extensive testing on the platform and pioneers like Jim down in FL did some extensive testing in the past year. Lotta good info out there.
03-03-2007, 02:38 PM #8
Awesome thread! I might be picking up a 2000 XL 1200 LTD from a guy in Long Island if i can get it for the right price. It has high hours though at 170. I guess I just need to factor in the cost of a top end sooner than later.
It looks like you might be hearing from me again, Carl! Long time no see.
04-02-2007, 12:57 AM #9
- Join Date
- Mar 2007
hey jim, how much is the shoe upgrade? also i am looking foward to seeing the ride plate i ordered from you up here in old hickory tennessee sometime this week, if it helps out on top end like everyone talks about i got 4 guys ready for them.
04-02-2007, 08:53 PM #10
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