2005 RX1 Mono Shock Suspension Durability Results

[Moodeyblue]

after reading this discussion, I looked at my /05 rx1 with 1200 kms and everything looks o.k. It does look weak at the idlers, but when comparing it to my 2001 SRX, I noticed that the SRX has 2 bolts securing the idler blocks to the rails (the 2 wheels @ the bend on the rail... instead of 1 bolt on the RX1). This would help strengthen the rails where the wheels are located and reduce the torsional forces @ the rails. I bet this will be Yamahas fix?

 

[ReX]

I snow checked a Apex but after listening to you guys I'm really concerned of my decision.

They have done a fair bit already to improve things:

- 06 sleds have grease fittings everywhere in the skid (this is probably the #1 thing that killed my suspension)
- 06 sleds are using slightly stronger bushings in the high wear areas (most 05's were updated too)
- 06 sleds have rail reinforcement brackets on both sides of the rail that extend to the middle idlers (where they break). It does greatly improve the situation, including over high miles (I can't say how I know, but it does). I doubt my rails would have cracked (in over 10,000 aggressive kms) if my sled came with them.

The major remaining concerns I would have is the front pivot arm (w-arm) and the rapid bearing failure in the idler wheels. I still expect Yamaha will ship the 06's with a strengthened pivot arm, but I've asked customer service and have been told they are not aware of any changes yet. The 06 sleds have rubberized wheels (thin layer of rubber), but they don't really last any longer than the hard plastic ones. They are quieter and ride a little better on hard surfaces though.

The other area that should be improved is the front suspension should be greased at the factory. I would expect that my front end would be in reasonable shape if it had been (of course you can take it apart and grease everything yourself if you like - I would have had I known nothing was greased).

As far as non-suspension issues, I did have problems with the crankcase ventilation system freezing up on my 05 (until I built a heater for it). The 06's have addressed this problem by heating the vent using hot crankcase oil. Other than the suspension and that my 05 has been bulletproof - zero oil consumption, great fuel economy, no smell, etc., etc. Once the suspension is fixed these should be fantastic sleds.

Hopefully Scooby (with 50% more miles than mine) can elaborate on the H-arm and A-arm problems they had. I haven't had any yet (other than my rear pivot arm assembly and front suspsension bushings are worn out from lack of grease).

 

[MrSled]

Rex, I want to see some pics of your broken arms on your 05.

 

[ReX]

Rex, I want to see some pics of your broken arms on your 05.

OK.

It starts out with a hairline crack that initiates along the weld, close to the middle of the flat section of the u-bracket that is welded to the tube (at least the current one is failing this way). The crack then grows through to the inside of the u-bracket and then progresses in both directions along the weld. On my first arm, the top broke through first.

The attached picture shows one of my arms with the break all the way through.

 

[ReX]

If you don't catch the break at this point in time, the bolt quickly fails in fatigue too (loaded in single shear). At this point, the broken piece falls off and one slide rail isn't supported at the front any more.

That rail also shifts forwards (bending other suspension components) and the track becomes totally out of alignment and only tensioned on the connected side.

I highly recommend catching the failure before it gets to this point (we were on a 7 day saddle bag trip and the build up of snow and ice hid the damage until it was too late).

All 3 pivot arms failed or are in progress of failing in the same way.

 

[ReX]

Here's a close up of the break. You can clearly see there is no bending to indicate any loading above yield and that it is a classic fatigue failure

 

[Sled Dog]

And they are putting these in all the 06's. Someone is going to get killed and Yamaha will have a libel suit on their hands. This is beyond bushings the skid cant handle the working stresses asked of it.

 

[ReX]

Hopefully this will help some of you catch it before anything more than the arm itself is damaged.

IMO, once Yamaha fixes this remaining issue (it should be a fairly easy thing to fix) as well as the premature idler bearing failure, these sleds will

 

[donbarb]

trouble with 05 mono shock

I am at present replacing all plastic junk bushings with oil lite bronse bushings. I am also putting in 7 grease fittings were Yamaha should have. I am also groving each shaft for grease to travel and also groving each shaft totally around at the point of the zirk attachment point. Every idler was seized on the skid and even the carrier wheel bearings for the track were completly shot. total hours for something that yamaha should have done in the first place [8] x 65.00 per =520.00 dollars thankyou Yamy!!!

 

[RX1-er-2005]

Where did you get your oil lite bronse bushings?

 

[ReX]

Re: trouble with 05 mono shock

I am at present replacing all plastic junk bushings with oil lite bronse bushings. I am also putting in 7 grease fittings were Yamaha should have. I am also groving each shaft for grease to travel and also groving each shaft totally around at the point of the zirk attachment point. Every idler was seized on the skid and even the carrier wheel bearings for the track were completly shot. total hours for something that yamaha should have done in the first place [8] x 65.00 per =520.00 dollars thankyou Yamy!!!

I wouldn't groove the shafts to let the grease travel. Just locate the fitting near the center and the grease will get pumped to the ends.

Ideally remove the arm and shafts, drill a hole, weld a nut to the surface of the tube over the hole, spray on some touch up paint and install a grease fitting. No grooving, turning, etc. of the shafts.

IMO the stronger bushings and adding grease fittings are a good idea. I'm convinced that part of the pivot arm problem is due to the relationship of the front/rear bushing condition. Typically with my skid, all the bushings would wear to some extent with the pivot arm ones getting completely shot. Then the pivot arm bushings would be changed under warranty, while the rear bushings wouldn't be touched.

The rear pivot arm then is still sloppy and effectively doesn't help locate the skid laterally under the tunnel. Now the front pivot arm is taking on even higher loads, including a large bending moment trying to keep the back of the skid in position.

I've noticed that the cracks in the pivot arm seem to form quicker when the rear pivot arm bushings and sissor shafts/tubes are worn and the front pivot arm bushings are new (the cracks still grow, just at a slower pace, when all of the bushings are good though).

 

[MrSled]

Thanks Rex...now I know what to look for...

 

[zoomzoom]

I hate to say this but I used to do 1500 miles per year on my Polaris and I wasn't looking at anything like this until the sled had 4000 to 5000 miles on it.

Have I been naive or is this literally extremely poor engineering from one of the strongest engineering companies (Yamaha) in the world.

 

[BADSLED]

Is anyone from Yamaha ever come to this site and look at any of these concerns many of you are having??? These W-arm failures are going to make a difference if i order an '06 or NOT when I attend a show this coming Thursday. I will bring these pics when i go and will want definate assurance that this is been addressed otherwise NO THANKS!! and I'll resort to a CAT suspension for my '04 rx. Yes, I know about cat's reliabilty overall but their skids can take one hell of abuse!!

 

[Sled Dog]

Get back to us with what they say.