How's it going guys. My Pilot with a 700 triple swap is developing a vibration. It only happen when there is some type of load. I can be cruising 50 and let off and the vibration goes away...but as soon as I touch the throttle it comes back. Had talked to another sled Engine swapped pilot owner who is having a similar issue and neither of us cant figure out what it is. Any info would be appreciated! Everything seems tight and right so I'm very confused

think I see your vid on facebook that thing sounds mean as hell..

as far a vibration, you think its coming from the Engine, gear box, or wheel, probably not a wheel if its only under load..could be one of your clutches is out of balance, could be a crank bearing as well.

Yeah I have posted a couple videos on the pilot community page on facebook. The last one was one in the sand! And how do you check if they are balanced or not? Hoping it's not a crank issue. Wouldn't it be running shitty if that was the case?

honestly not sure how you would check a clutch for balance. also check the belt to see if it has any missing rubber.
a bearing won't make it run shitty. until it explodes..

Yeah pretty sure it's the transmission bearings. Don't really know what to do about it. A buddy from here thinks I can rebuild it but I just have 0 confidence in my mechanical skills to try and pull that off lol

get a manual and follow it..you might surprise yourself

pull the belt off and grab the driven clutch, see if you can feel play, I had mine go out, the bearings for the upper driven shaft are not available but there are a few options but I would say you need to mechanical aptitude to pull it off. I'm having some bearings modified now should get them this week.
if it is the trans, they can be found on ebay from $600 to $1300.
I'm thinking the input shaft needs more support with an extra bearing.

Bumping this one. Both my pilots have pretty loose driven clutch shafts. My rotax 600HO pilot has worse.

Rotax 600HO Pilot Driven clutch measured at the end of the shaft
Radial deflection: 0.037"
Axial deflection: 0.028"

Thoughts?

Interesting!
If it happens only over 50 or so. I would rule out crank since we're using a cvt. Engine rpm's high at low speed as well.

On the gas when it happens or under load at a given rotational speed of the drive train.
If you let off the gas it goes away the speed is still there. So under load it is.

Conversions has a higher rpm and applied power than a standard pilot. If these issue bare cropping up after a little time I would say it's a wear issue. If it had the issue from the start either it is already wore or something is out of balance or alignment.

Then there is tire choice and terrain. Rolling load verses pulling load. Sand tires would be pulling load. Standard tire would be a rolling load.

So step one change tires and see if it gets worse or better. Then ride on payment then dirt and then sand and compare.
If happens on pavement look for an out of balance issue somewhere in the drive train.

Last check the distance between drive and driven and run out on both clutches.

It may be a frequency issue which is not good on parts.
Most of our axles are pretty worn and trans have a lot of wear.
The only other thing on the drive side would be the drive clutch. I would check there first and make sure all is good for your type and set true on crank.

Some first thoughts.

Radial deflection: At this time I'm going to discount this one. The reason I say that is because I don't know what kind of gorilla is yanking on the shaft and how hard you are pulling ( ). I'm a small guy ( ) and can deflect a 2 7/16" line shaft with a 3' bar at work. So for now I pass on this info.
.028" axial may not be a lot depending on the set up.

Axial deflection: This one is concerning. --- .037" seems like a lot to me. This also MAY not be an issue but I don't like it. The best we can do here is get someone with a Pilot to take these measurements on their machine and report back.

CO

Since I'm here right now I'd like to address the title of this post.
Vibration under load:
This has happened to me twice since I've owned my FL350's.
Both times it turned out to be Engine rubber mounts. They were worn out. The vibration was bad and concerning at the time. You will know because the whole frame under your azz and in the seat shutters and you can feel it in your back. Also the steering wheel vibrates.
CO

Axial deflection is .027". that's push/pulling the driven straight out of the tranny.

I have a regular FL400 pilot also. Both my FL600 and FL400 pilots have very similar deflection at the driven shaft. I bring this up because I blew a drive belt on my FL600 yesterday. I also have an FL350r, and boy - that sucker has got about 0.060" of axial deflection!! Yikes. At least it self-aligns the clutches lol

Blew a belt. No surprise.
The thing machine has a new found power band.
Bet it felt good even though you smoked one