anyone covert there WD to a Makuni

milkman · Post by **milkman** » Sat Dec 27, 2008 5:32 am

Very frustrated here trying to get my X4 to run, and a guy told me that this would be the easiest way. I found a kit for $150. w/ everything I need but I wonder how they really work.

Mike

Post by **Matt** » Sat Dec 27, 2008 10:02 am

What is included in the kit? You would need new choke & throttle cables, a flange mount, and a fuel pump.

Would it be easy? No. You have to figure out correct jetting on a Mikuni, which means taking the sled for a run, checking performance and spark plugs, then taking the carb back apart to change jets, put back together, make another run, check plugs, change jets, put back together, over and over until you get it right.

400brian · Post by **400brian** » Sat Dec 27, 2008 3:33 pm

and....to get full throttle, you'll have to replace the right side handlebar grip with one off a Mikuni equipped sled, they have the increased throw to make it work.

Post by **ICCSF 108** » Sun Dec 28, 2008 1:39 am

If you purchase a new Mikuni carb for a snowmobile they are usually jetted close to what you need.
such as
VM 28 - 210 main
VM 30 - 220 "
VM 32 - 240 "
VM 34 - 260 "
VM 36 - 320 "
VM 38 - 360 "
VM 40 - 500 "
VM 44 - 530 "

This would Just be a starting point & on the VM 28 - 34 depending on your engine size could be on the lean side???

Kenny

The Hunter · Post by **The Hunter** » Thu Jan 08, 2009 11:11 pm

If I wanted to do this on a 77 Kolher K295 engine which one would be the closest, do you think?

speedy295 · Post by **speedy295** » Fri Jan 09, 2009 12:23 am

I'm not sure what is on like a trailfire, but I would maybe try that or the next size carb, you can probably use that for jetting guidelines to.

I would say your going to want a 30-34mm carb. I would start by looking for some sort of a low performance 300 and use that as a baseline.

S_Kyle · Post by **S_Kyle** » Fri Jan 09, 2009 1:38 am

We used a 34mm off a cyclone on my friends 75 300, not sure what he changed for jets but works great. Just don't expect to get very good fuel economy out of the sled once you switch to a mikuni

speedy295 · Post by **speedy295** » Fri Jan 09, 2009 3:25 am

Why not? if its jetted correctly it should do even better. A mikuni is light years ahead of a walbro, or bendix.

S_Kyle · Post by **S_Kyle** » Fri Jan 09, 2009 9:55 am

It is my experience that Deere with non powerjet carbs seem to get poor fuel economy. A mikuni is a much better carb than the old walbro's and Bendix's but use a lot of fuel. The 300 riding along side a 400 with a Bendix uses a significantly greater amount of fuel. Just my experience.

Scott

Rodimus Prime · Post by **Rodimus Prime** » Fri Jan 09, 2009 4:17 pm

400brian wrote:and....to get full throttle, you'll have to replace the right side handlebar grip with one off a Mikuni equipped sled, they have the increased throw to make it work.

nope on the handlebar you will see space to drill a new hole and reposition the stock throttle lever.

400brian · Post by **400brian** » Fri Jan 09, 2009 4:25 pm

As RP pointed out, , some of the hand grips have the required space to relocate the hinge pin, earlier ones do not.

_FIII · Post by **_FIII** » Mon Jan 12, 2009 12:00 am

in the process of putting one a 300 right now. Used the specs from page 3 of this chart

http://www.bayshorecad.com/Sleds/Literature/Carbs/MikuniVM/Mik_Conversion_Specs.pdf

It runs decent but we are having problems with it once it warms up to operating temps which leads me to believe that it is a little rich still.

VM-30

main 270
pilot 35
needle jet 159 Q-O
needle 6DH2-3
throttle slide 2.0
needle and seat 1.5

Does anyone have any experience with doing this?

1977JD300 · Post by **1977JD300** » Mon Jan 12, 2009 10:50 pm

I just finish converting a 77 300 to a mikuni, i used a carb off a mid 80's ski-doo safari 377, the flange has the same spacing for the bolts as well, the holes just need to be drill slightly larger, it does run slightly rich but not bad, will foul a plug once in a while if it idles for a while but that is not serious, other than that it is great.

milkman · Post by **milkman** » Fri Mar 06, 2009 4:57 pm

Anyone else??? I will be doing this swap this summer more than likely, but if I could find the right carb(maybe somone on here has one?????) I would do it now.

Mike

The Hunter · Post by **The Hunter** » Fri Mar 20, 2009 12:49 pm

I have a mikuni vm-34 (don't know what sled it came from) running my 300. Works good. Every one in a while the PTO side spark plug fouls? and no longer sparks. I think it is from weak ignition, as the plug still works fine in any other sled.
It's kinda hard to hard at -15C, but it does go eventually