• We are no longer supporting TapaTalk as a mobile app for our sites. The TapaTalk App has many issues with speed on our server as well as security holes that leave us vulnerable to attacks and spammers.

06 Apex mtn mcx build.

Nice! machine. Nice riding area! Pics are beautiful. Very similar to what we have here, but looks like you are a little more mountainous, have larger fjords and have a few more trees.

Greetings from Nunavut!

My Easter weekend, I had to work. This was on Saturday during the Iqaluit-Kimmirut-Iqaluit snowmobile race. My check point.

Yes the scenery is amazing to ride in. To bad I don`t get to do as much riding as I would prefer..

Got a few more km`s this last weekend. At friday night I blew a belt for the first time. I were going across a lake trying to catch up to a buddy, and were powering up to 10500-11000 rpms when it blew. So it hit the limiter hard. I were quite worried that something had broken, but it seems like only the belt blew. It was a serious pain in the a.. to get the debris out. All the rubber was scattered around and the thread inside the belt had mangled itself around the helix. We had to get a crowbar and some pliers to get it cleared.
Are there any tools that are made to compress the driven pulley when that happens (or just to change belts)?

Some pics:

Primary, easy to clean

secondary, pita to clean. The spring is so stiff..

overall, lots of debris everywhere..

Maybe not so bad that the belt has lasted this long. It has been on since the sled was new, that is about 3750kms and 11 years..

Sunset on the mountain





btw: if anyone wants to chime in, please do:

"The sled pulls really hard, but if I´m not really careful with the throttle it goes on the limiter. Is there any other ways to avoid this, than adding more weight? Is it possible to reduce the boost at the top of the rev range?"

Is it hard to use to mcx logger and software to fine tune the boost?
Last edited:
Upgrades on the way.
The sled was until now widened to 45" with a pioneer performance kit (stock was 38?, as it is a mountain model) with fox floats. But the widening kit was made for stock shocks, so they were mounted a bit inwards on the a-arms. This made the sled a bit tippy, so now we are going for stock apex width at 42".

First ride this season:

One from last season, shows more of the M-skid (as photobucket removed all the old photos..):

one more:

"new" front end. Stock width, oilite bushings and ttx shocks. Had to order new bolts and collars for the spindles as the old ones were bent and broken (expaining the hex key as a temporary "bolt" on the temporary spindle). So now I`m waiting for parts..

old front end:
lookin good.

thanks for reminding me to check lower a arm bolts this year. looked like a w 2 years ago when i put the oillites in it.
Ha-ha, yes.
It`s the only cover I have that fits unfortunately. The riser is so high, and the air inlet at the back makes the oem apex cover not fit at all, but this one almost does..

Well due to insane amounts of snow lately, danger of avalanches (they go everywhere now) and incredibly flat light I did not get to ride much. Easter was over wednesday, back to work.

But the "new" front end was a great improvement, sled is much more stable now.
Btw it started to smell of oil again, so I have to check those oil return lines again.

Is it normal for the yellow oil warning light to come on while sled is almost upright? It did when i got stuck on a hill..

Lots of fresh powder, and this was before the most snow came:

One of the bigger avalanches, caught one of the few times the sun showed up (sled trail is right through the middle of it):

Flat light:

And more snow incoming:
Not much updates lately, and not much driving.
Been struggling with smoke from the exhaust (oil leaking through turbo seals).
Checked all hoses for kinks and interruptions. Found one by the engine (see pic below) that was kinda kinked, and fixed it by relocating it above the intercooler support. But it did not stop smoking. The pics below shows the smoke after shutting the engine off..
I guess that next time we go to the cabin, I´ll have to check the oil return pump. Has anyone had issues with that pump?



I commissioned new seat covers for my Apex from Nithrone. They are the first Yamaha snowmobile covers they have done, and I can’t wait to get them home, and choose one to install. I think I will go with the yellow one. They are just finished, got some pics today. What do you think?

Finally got the apex finished before last weekend. It felt good to get on the boost again.
Since last time I installed one of the new nithrone seat covers. I think it may be too bold, so looking for a new seat to put the other cover on (if anybody in norway, sweden or finland have a spare seat, let me know...). I also checked the oil return pump and the return hoses and everything were good. So I tink the oil problem may have been the seat pinching the return hose, so i cut a bit more off underneath, so far so good. I also installed a belt change device from rich motorsport (?) which you can screw in a bolt/handle to separate the secondary.
On the last day of riding I had a problem with the sled letting of boost at 0,5 Barg and stuttering. I did not find anything wrong after a checkover, and afterwards it worked fine. Wonder what that could have been. Made a separate thread in the turbo section, hoping for some tips/pointers/suggestions.
Have made enquires to m&m racing about a clutch kit, as I hate that it hits the limiter when giving it wot from low speed.
Last edited:
Greetings from Finland! Nice to see these old ones still running. We have two apex 163" builds, other is my brothers with t-motion skid and now we are adding some mpi charger kit in it and drop and roll chaincase, new front end and steering also. Other one is mine and my daughter and wife drives with it, it has lynx boondocker 4100 skid and some other minor mods on build. For your clutching troubles there is simple solution, you have to change your way to load your supertips. Heaviest tungsten weight on tip of the weight, so it works as much heavier weight. There is many ways to use these weights and I like using these on my turbo nytro. Other easy way is to just loose some tension on secondary clutch spring, it helps a little. There is some videos in youtube with my username of my sleds. Keep up good work with sleds!
It`s been a while.
Had troubles with the plate underneath the turbo, that kept falling off. So made up a larger plate to mount instead of having two plates. And when i had the rivet gun in use I mounted the aluminium hose guards at the back of the frame.
The stuttering issue went away by itself :dunno:, at least it havent been a problem since the last posting.
Haven`t done anything about the clutching issue, but it works good if I am careful with the thumb.
Then it worked well for a while, so got to use it a bit.
Then one day it started running rough (see video link below), like it was running on 3 cylinders. So I changed the spark plugs to see if it helped. But it didn`t. I found that one of the black mcx 450 injectors were stuck open (see video link). So that was it for this season. Guess I`ll have to get new injectors, do an oil and filter change and some other miscellaneous maintainance before next year.
Here are some pictures (and videos) from this year:

new plate installed:

After mounting the plate, testing to see how it works, before reassembling everything.

Evening ride with the wife


Faulty mcx 450 injector:

finally got the protectors mounted:

Video of the injector in action:

video of it running rough:

video of it going up a hill:
Last edited:
Thanks Kinger.
Yes, glad i found it! Hopefully there isn`t any damage to the affected cylinder..
I only use fresh premium 98 octane (like your 93 i think) on my Apex, no additives.
I were in contact with Erik at Mcxpress, and he said that they used the black junri (china) injectors only for a short while. They reverted back to green bosch injectors for all builds. So I`m getting those this summer. I also have to have the mcx box remapped for those injectors.
We usually go for holiday in the area where Mcx are located, so I`ll pop by them to collect the injectors and have the remap done while I`m there.