16 270 mxu is a pos!

[Stig / Major Tom]

U can't call kymco for Any thing they would not tell me a thing but contact your dealer. Thats bs. No other reputable company would say that to a customer. 

Did you research your machine before purchasing?
Off-road at 32mph not enough for a youth ?? 
Might explain why KYMCO is reluctant to offer phone advice to a DIY'er who 'needs' more speed from this machine. You're modifying their T-14 product.
Stig

[Notch352]

Well they shouldn't have bs dealers to tell customer oh it's twice as fast as the 90 derestricted. No 32 isn't fast enough for trail riding. It's MY MACHINE last time I checked who said anything about modifying who wants to spend 4k for some pos machine that goes 14mph my  lawnmower is faster.

[Bratman2]

Seeing the picture it would look like the two thick washers would be removable. Is that not so? The 270 is a fairly new model so a lot of information on the forum is not available because there is not that many around yet. I can't imagine why just changing out the boss causes it to start making a rattling/knocking sound if reinstalled properly. Did you makes sure the belt was not pinched when torqueing it down? Did you make sure all the roller weights were held in place when reinstalling?

That part you ordered would seem to be the correct boss to derestrict it. You would want the sheaves to go closer together to raise top speed. It doesn't pinch the belt as the weights when spun push the sheaves together and the belt rides up the sheaves to raise the gearing higher. Why don't you try this. Remove the cover on the cvt. Block the rear wheels up and test run it some and see what is causing the knocking. You can also check for full belt travel.

[Notch352]

It dosent make that noise all the time only once in a while usually on decell.  Yes the washers are removable and was told by dealer u can take those off and get 32mph until the boss face arrived then to install that to get to 38mph so I did that but still can't get over 32mph with speed screw out to 15.3mm max allowed. The new drive dosent have that spacer welded at end so it's 1/4 in shorter so it squeezes everything tighter. I used a impact to to tighten the bolt is there a certain torque it needs to be tightened to? I didn't tighten it super tight but it is prolly at 30 40 ftlbs

[Bratman2]

Not sure on the 270 but I seriously doubt it is much lower than our MXU450. The MXU 450 calls for 147ft. lbs. of torque and also requires red locktite. It may very well be working it's way loose. Which if it does come off can be terrible and cause a lot of damage inside the housing. I recommend you shut it down until you have time to get locktite  and torque it much higher. I don't like guessing on those numbers but Arctic Cat also sells the 270 under their name. You may very well find more information about the 270 searching under Arctic Cat online. It would be shocking to find that the CVT was any different. I am running an Arctic Cat XC450 cvt sheaves that have been machined for faster acceleration in my MXU 450. I would also leave the cover off and either block it up or ride it yourself and look over the CVT system to make sure everything is right, Then install the cover. I would not allow anyone else to ride it with the cover off as that can be dangerous.

Let me edit that, Arctic Cat calls it as a 300 but it is the Kymco 270 motor, drivetrain.

Last edit, :https://support.countrycat.com/posts/1420615-2017-alterra-300-service-manual
That should give you the information you need for torque values, it is considerably lower than the 450 but higher than 30-40. Hope that helps you out some. Only other thing I can think of is maybe it needs to break in some. The speed should be 38 with the drive boss you installed. I have a niece with the Kymco 300. I'll try to get up with them and see what theirs will do.

[souzamoto]

If you installed the Mongoose/MXU 300 drive boss correctly, you can remove the limiter screw completely.
After that, if it still wont go above 32, you've assembled it incorrectly.
At the least, contact your dealer and ask them to forward the pages from the service manual related to clutch disassembly and reassembly. There is no in print manuals available from Kymco in the USA. They use cyclepedia. You can also subscribe to cyclepedia and have access to all manuals.
The only difference between the mongoose 300 & 270 is the designation and the restriction.
There is no other restriction except for the clutch.
The Mongoose 300 engine was always a 270cc.
Kymco has sold more 270's than 300's due to the low age requirements.
CJS

[Notch352]

Well common sense would be if a 90 unrestricted can do 30 a 270 should do hell of a lot more it's almost triple the hp. I bought because I didn't want to buy him another one in 2 years but that's not gonna happen.

[Notch352]

Not sure on the 270 but I seriously doubt it is much lower than our MXU450. The MXU 450 calls for 147ft. lbs. of torque and also requires red locktite. It may very well be working it's way loose. Which if it does come off can be terrible and cause a lot of damage inside the housing. I recommend you shut it down until you have time to get locktite  and torque it much higher. I don't like guessing on those numbers but Arctic Cat also sells the 270 under their name. You may very well find more information about the 270 searching under Arctic Cat online. It would be shocking to find that the CVT was any different. I am running an Arctic Cat XC450 cvt sheaves that have been machined for faster acceleration in my MXU 450. I would also leave the cover off and either block it up or ride it yourself and look over the CVT system to make sure everything is right, Then install the cover. I would not allow anyone else to ride it with the cover off as that can be dangerous.

Let me edit that, Arctic Cat calls it as a 300 but it is the Kymco 270 motor, drivetrain.

Last edit, :https://support.countrycat.com/posts/1420615-2017-alterra-300-service-manual
That should give you the information you need for torque values, it is considerably lower than the 450 but higher than 30-40. Hope that helps you out some. Only other thing I can think of is maybe it needs to break in some. The speed should be 38 with the drive boss you installed. I have a niece with the Kymco 300. I'll try to get up with them and see what theirs will do.

Wow I think I'd snap the drive in half if I tryed to torque that high. It came off pretty easy and didn't have any locktite on it I didn't wanna go to hard and break it. I'll go put at 75lb and see if it helps I only took it around the corner and back. Thanks for help

[Bratman2]

I gave you the link to Arctic Cat's 300 service manual. It calls for 70ft lbs. It also gave the procedure for pulling and reinstalling the drive belt and cvt system. I would recommend reading it. It is only a few pages down from the top when you open the link.

[OldDirtDude]

Just replaced the drive boss on my sons MXU 270 with the one from the 300. I got it to 47mph before I let off the gas but it was still climbing This thing now has serious fun factor.

[CROSSBOLT]

Sounds like you got it right, Old Dirt Dude! Too bad Notch is not around to hear your good news!