My XL1200 LTD 4 stroke conversion

[riderroads]

Hi All,

Picked up a 1999 Yamaha XL 1200 LTD a couple weeks ago and will be doing the MR1 conversation. Picked up a doner motor and already have that apart in the garage. I will be documenting my progress here.

Looking forward to this project as I have always like these hull's when they came out and never got around to picking one up.

Later,

Eric

[riderroads]

One question I do have - I got the FX fuel tank as it fits in the front better - are the FX and VX fuel pump's interchangeable?

Thanks

[riderroads]

Big week this week in terms of paperwork - got the title and registration for the ski together.

Installed the FX gas tank.. its like it was ment to go in there, got new steering and reverse cables, plus picked up the rest of the electronics.

I also got the driveshaft , and VX pump. Just need a few more parts but coming along nicely.

Motor is apart and waiting on a box to rebuild it - coming in this week. In the mean time will start by giving the head a valve job and getting that all sorted out.

[Mr. GP1800]

Looks like a cool project. Look forward to seeing the progress

[riderroads]

Hi All - Been making slow yet steady progress on the ski. Figured out how I was mounting the dash, got the pump and everything lined up (including installing new cables and my cable extensions came in) , along with getting the motor together. The original bearings all were within spec but changing them out to new anyway. I sent the head to the machine shop as it needed some help and hoping to get it this week and installing the motor as well.

[riderroads]

Hi Guys - well made some progress this week - Been busy with Work, took a small vacation, and got the house painted.... but managed to get the motor put together, head back from machine shop and installed. It this weekend. It went in very easy!!! More to come.

[riderroads]

Really big update today.. She lives.. rebuilt motor sounds awesome.. Some electrical issues to narrow down... ie found a corroded wire for the start button.. need to solder that... The Fuel pump was not getting 12 volts.. more like 8... so once I jumped that along with start button she ran.. Have about ten minutes on the new motor at idle... Sounds great... Now I need to finish it up, and pick up a double trailer and get her out on the water. I had my hands full to get any pictures or video.. More to come!

Later,

Eric

[riderroads]

Minor update - found out why the fuel pump was not getting 12 volts... bad grounds at ground block.. I took care of that as well as provided a second ground to the battery. Unfortunately the fuel pump was not making good pressure (10 psi while cranking) .. New pump should be in this week and crossing fingers that's all it needs.

[riderroads]

Big News tonight.. Fuel pump and regulator came in.... put it together and she fired up on the first button press... Sounds great!!!!


Ski Running Video

My issues were:

• Bad start/stop switch
• Bad grounds
• Bad fuel pump/regulator

Now I gota pick up a double trailer and get it tested!

Later,

Eric

[riderroads]

She runs beautifully. Picked out a double trailer (actually got lucky and traded my single + some cash for a double) , cranked the ski on the trailer and off we went. Since I rebuilt the motor I was following Yamaha's break in procedure during the lake ride yesterday. Couple things I needed to adjust like I do not have the steering straight and I need to plug up the holes where the fuel selector and choke nobs were.

Running

Overall this wasn't a bad swap.. If I wasn't rebuilding the engine it would have gone super fast.

[Myself]

Nice job on this.How does the top speed compare to a regular VX?

[riderroads]

Thanks.. I wasn't running too much up top as I was breaking motor in.. but with that said.. feels about the same as a VX... I think I saw 50/52 once but stayed at 40 and below most of the afternoon. I am running a VX stock impeller and pump.

[riderroads]

Some Pictures of the Motor in the ski:

I cannot believe the motor mounts lined up and with the front cover removed installation was very easy. Getting to the fuel pump is very easy (I had to change it out as my used unit failed) along with all the wiring for the dash.

2014 VX Pump with 2 inch FX extension to fit the 2014 driveshaft with OE VX impeller.








Oil tank - plenty of clearance to get to oil fill... also installed the oil separator on the firewall where the factory 2 stroke ECU was located.


Motor has a manufactured date of 2015 - I had the head machined as it had rust on all the exhaust valves. You can tell this motor sat as 2 of the four pistons had stuck rings. Reused the factory pistons as they were within spec, new rings, all new bearings and gasket kit + a new fuel pump.


Mounted ECU plate on the rear firewall near battery.. plenty of room to run with factory VX harness.



One problem that I had that was driving me crazy was the ground block. I would get intermittent connections causing a few headaches. No matter
how much I cleaned it or pried the pins it would do the same.. I cut them off and grounded everything to the oil tank bracket. I also added a second
ground from the battery to the oil tank bracket.



Now that I have spare parts I am thinking of doing a second. I have a spare block that needs to be machined sitting in my garage.

Overall I am very happy how it performs, and the fact it starts in like 2 seconds cold or hot is wonderful.

Next up for the 1999 XL 1200 LTD is paint correction and factory graphic restoration.

Later,

Eric

[riderroads]

Actually got to go fishing off the Ski... ran great until I ran over a matt of that seaweed thats invading us and got an overheat warning... ski went into limp mode.. least I know that works... went swimming to pull all the junk out the intake, waited five minutes, started it up and was good to go.

Caught a bunch of trout.








This ram mount cup holder was the MVP... It also filled one of the two holes.... I am installing a pod type stereo next and the remote volume nob will actually fit perfectly where the fuel selector switch had occupied.

Hopefully she runs like a top for a long time. Next up is to put a few more hours on it, changed the break in oil to synthetic, and work on paint correction, change traction matts, and recover seat... But that's all easy stuff that will just happen over time.

Later,

Eric