Apex Torque Limiter?

[Yamahammer485]

Hello all

I have a serious issue with clutch alignment. When I replaced my flex pipe donuts, the aluminum sheild over top had contacted the motor repeatedly due to movement under power. The motor moved so much that it bent the corner of the sheild.

Using ulmers clutching tool, and checking center to center and offset, It says that I am only out a about 3-4mm on ctc, but to have it move so much suggests that maybe a motor mount is either really loose or broken.

I am just wondering if anyone knows of a torque limiter for the apex that works? There is one in the tech section, but there is controversy about it as it has a lack of flex and could snap the boss on the motor. See links...

http://www.totallyamaha.com/snowmobiles ... nelink.htm

http://www.ty4stroke.com/viewtopic.php? ... ue+limiter

Also, can anyone tell me where the rear motor mount is on the apex, as in a picture. I have looked at microfiche and a break down of it, but a picture would be better, just so I can understand how to use a special tool developed by a member to adjust the motor mount. Here is the link to that

http://www.ty4stroke.com/viewtopic.php? ... t+clutches

Any help would be appreciated!

 

[Yamadog]

Also, can anyone tell me where the rear motor mount is on the apex, as in a picture. I have looked at microfiche and a break down of it, but a picture would be better, just so I can understand how to use a special tool developed by a member to adjust the motor mount.

The mount is a bolt that runs the entire width of the back of the motor. There is no special tool required. There is an end cap on the nut side of the bolt that is threaded into the motor mount that needs to be loosend to create room to slide the motor out. You can tighten that with a large flat end screw driver when the motor is install with the bolt is in place.

The front engine cradle for both the RX-1's and the Apex's are the same setup and the motor mounts are not what you would find say on a 2 stroke motor but instead is cast as part of the motor and has a rubber bushing for shock dampening but there is no real room for movement when the engine is installed. Alot of the older setups bolted the motor to the floor of the bulkhead and the torque would cause the motor to rotate on the pivot poit like a top causing rotational stress on the mounts, and because they were 2 cylinder 2 strokes and vibrated badly used large rubber mounts to isolate the vibration. These 4 strokes are smooth and do not require that dampening so the dampening requirement is greatly reduced.

I would think that you have some sort of damage to the front bulkhead or flex between the bulkhead and the tunnel, if the motor is moving enough to bend that heat shield.

 

[Yamahammer485]

Here is a pic, I couldnt upload earlier

The bottom pic is of where the plate rubs on the motor

 

[Yamahammer485]

Thanks for the reply yamadog!, I am going to really have to inspect for damage. Should I be looking more for cracks or a larger damge?

 

[Yamadog]

Your pictures are not coming up but I really can't see how you would have that kind of movement without some other issue.

I have grenaded 2 motors in the past 2 years and with the number of times I have pulled and replaced motors I just can't think of how the motor would be moving that much without some other flex between the tunnel and the bulkhead.

I have buddies running 300 hp turbos and there is no movement in the engine bay.

Did you buy the sled new? and do you do a lot of ditch banging or jumping? even so I have never seen anyone damage the delta box without a mojor hit.

I hit a 4' tall frozen dirt embankment at over 100 mph and ripped the A arms out, busted the front of the bulkhead and destroyed the tunnel but did not hurt the engine compartment.

 

[Yamahammer485]

Sorry for the delay, here are the pics

Also, I was just wondering what you thought if maybe I seen a hairline crack on the motor mount behind the secondary? It might not even be a crack, its that small

Also, in the last pic (right side of battery box "PTO side" motor mount), that bolt is tight, but should it stick out that far? The other one is exactly the same.

The pic of the motor shows where it was rubbing.

Im thinking of calling yamaha canada, because the motor moves so much to bend the metal sheild, its a big amount of force to do that. Now would be a good time to mention that I am a pro rider and never crashed, abused this sled EVER! Bought it new and has only been maintained by me.

 

[Yamadog]

Boy I would think that is way more movement than ordinary. I got the pics but its been since last season since I pulled a motor I can't remember how those bushings look on the mounts but I don't think it stuck out like that. I am working all day today but when I get home I will look at one of my pulled motors on the bench.

If I were you I would talk to Yamaha if you can. these delta box frames are so strong & the motor is wedged in and held to tightly I can't see how that result would be possible without some sort of mount failure.

I crashed an 06 at over 100 mph into a frozen 4' tall embankment destroyed everything except the engine and bay. I have bought 2 Apexes that were totalled the same way and tore them down for motors and never saw a compromise of the engine compartment.

 

[Yamahammer485]

Also, can anyone tell me where the rear motor mount is on the apex, as in a picture. I have looked at microfiche and a break down of it, but a picture would be better, just so I can understand how to use a special tool developed by a member to adjust the motor mount.

The mount is a bolt that runs the entire width of the back of the motor. There is no special tool required. There is an end cap on the nut side of the bolt that is threaded into the motor mount that needs to be loosend to create room to slide the motor out. You can tighten that with a large flat end screw driver when the motor is install with the bolt is in place.

The front engine cradle for both the RX-1's and the Apex's are the same setup and the motor mounts are not what you would find say on a 2 stroke motor but instead is cast as part of the motor and has a rubber bushing for shock dampening but there is no real room for movement when the engine is installed. Alot of the older setups bolted the motor to the floor of the bulkhead and the torque would cause the motor to rotate on the pivot poit like a top causing rotational stress on the mounts, and because they were 2 cylinder 2 strokes and vibrated badly used large rubber mounts to isolate the vibration. These 4 strokes are smooth and do not require that dampening so the dampening requirement is greatly reduced.

I am about to tear into this soon to try and figure out what is going on and was wondering if you had any pics of the rear engine mount? Im not sure on how I would need a large flathead screwdriver?

Also, havent contacted yamaha yet, but going to try my dealer tomorrow!

Thanks!

I would think that you have some sort of damage to the front bulkhead or flex between the bulkhead and the tunnel, if the motor is moving enough to bend that heat shield.

 

[apltx08]

Yamahammer485, Don't forget you're STUDDED like mad...this being said the TORQUE these 4 strokes have when you hook-up has to go somewhere, I ran a RX1 '05 w/12000kms and now a APEX '08 w/6500kms with no issues so far but I don't run STUDS so a lot of torque is lost due to spinning that releaves a lot of stress to motor mounts all this said maybe in your case you'd be better going to SOLID mounts like some turbo guys are doing would maybe solve your problem...

 

[SledFreak]

Yes, but he's not running power like a boosted sled it, so I don't see the studs being the problem.

Yamahammer485, did you send those pics to Ulmer to see what he thinks?

 

[Yamahammer485]

I actually talked to him on the phone about it and he says that he has never seen anything like that before.

Also, last season I only ran 162 studs

Thanks for the replies guys!

 

[**sj**]

okay...for a moment ignore the shield...lets talk about why you think you have an alignment issue...are you blowing belts...do you experience any bogging or other problems....maybe it isnt actually moving but the shield bend was caused by some other movement or> and the witness mark on the motor is from something else>?

 

[Yamadog]

okay...for a moment ignore the shield...lets talk about why you think you have an alignment issue...are you blowing belts...do you experience any bogging or other problems....maybe it isnt actually moving but the shield bend was caused by some other movement or> and the witness mark on the motor is from something else>?


Yeah think happy thoughts

Yammahammer I am sorry I didn't get back to you right away. I did look at one on the bench & I have no idea whats going on with that mount other than for some reason it is shot. The inner bushings on mine are tight and will not walk out like that.

 

[Yamahammer485]

Thanks again for the replies.

First off, I checked my alignment with ulmers clutch alignment tool and found it to be off quite a bit about 3-4mm ctc. During the year with a new belt and washed to remove residue, the clutches ran hot, too hot to touch.

I have never full out blown belts, but on both yamaha belts I have owned, I have had the cord pop out which runs about 2-3mm past the top cogs of the outside of the belt, possibly due to the high heat. When it comes off, it is like a stringy fuzz.

Another note is that I have never had a clutching issue like bogging or lack of power., and I always keep my clutches squeeky clean and never use harsh abrasives. I only use scotch brite a few times.

However, this is the biggest mystery ever and the only thing I can think of is simply clutch alignment as the culprit. It is how I used to run water with the sled, it could do miles of it without a problem, then it slipped for the first time. Then steadily after that, I could keep running less and less water before the belt would slip. Now it is down to 5 ft of water or slush and the belt slips. When the belt slips, the engine hits the rev limiter and belt in the primary hits the bottom of the belt cover.

I am starting to think that maybe either the clutching has slowly became out of alignment thus making the belt slip more and more easily, and/or the engine hitting the rev limiter misaligns the clutches.
This also started my first year with the sled and no power mods.

Also, I would like to see more apexs to see what their front engine mounts look like, as the ones I have seen all seem to look like mine, including the one from ulmer racing in the oil filter relocation kit instructions show.

www.ulmerracing.com

Click on instructions, then oil filter relocation, and there are some reference pics on page 6

Thanks again guys!

 

[**sj**]

everything you said about the belt indicates an alignment issue...and it isnt a regular occurance to go out of alignment....I am starting to believe a broken motor mount or the like..