Anti-bottoming kit

[RDPOWER]

yamaha canada has a anti-bottoming kit listed on there website for the apex - how does it work - has anyone tried it and do you like it -
http://www.yamaha-motor.ca/products/acc ... oryApparel

 

[pro116]

That's for torsion spring models only.Nytro,phazer,apex rtx,05 vectors.It goes on the rails and the springs hit it before they bottom giving them a little more tension just before bottoming.

 

[TurboTime]

That's for torsion spring models only.Nytro,phazer,apex rtx,05 vectors.It goes on the rails and the springs hit it before they bottom giving them a little more tension just before bottoming.

How well does this kit work or is it better to replace the spring with a big boy spring..

 

[pro116]

It really helpos alot if you ride agresssive if you are more than 240lbs I would recommend going with stiffer springs.

 

[ReX]

It really helpos alot if you ride agresssive if you are more than 240lbs I would recommend going with stiffer springs.

I would normally recommend stiffer springs to. Unfortunately I tried the "heavy duty" torsion springs last season on my 2007 RTX. For some unclear reason, the "heavy duty" springs are not only stiffer, but they are "designed" (according to Yamaha) to lower the rear end by about 2-3 inches (unloaded - loaded ride height dropped somewhere between 1-2" with me on it with the cam on high).

As far as bottoming resistance, personally I found the stock springs identical to the heavy duty springs. The heavy duty springs did firm up the ride and dropping the height may have given it a very slight edge in handling.

In my case I wanted to go the other way though. Taller primarily.

In the end, after researching this in depth, taking to Yamaha, Pioneer and Hygear, I ended up taking the stock springs to a shop and having them rearched to raise the rear end a good 5" (initially). This made a big difference to both ride height and bottoming resistance.

The anti-bottomers definitely help (first thing I tried), but they unfortunately increase the amout of rebound off bigger bumps. I'd recommend if you need the anti-bottomers, you should also revalve the rear shocks.

Hopefully Yamaha will improve the available torsion springs for next season. Apparently they have also made big changes to the shock valving for the 08 RTX (much firmer).

Note my comments above are for sleds with the ProActive skid (Pro116 listed them above).

For a monoshock skid on the other hand, the heavy duty spring works very well, but there are no anti-bottoming kits available.

 

[HAMMER]

The anti-bottom definitely helps (first thing I tried), but they unfortunately increase the amount of rebound off bigger bumps. I'd recommend if you need the anti-bottomers, you should also revalve the rear shocks.

I've also found the rebound is an issue with the anti-bottom kit. Really pisses me off when the seat comes up hard, hits me in the azz, and tries to pitch me over the bars. Unfortunately the Apex Mountain has junk shocks under it, front, and rear. I don't mind spending some money on decent shocks as I bought the GYTRs to put up front. My gripe is that I don't want to replace the entire rear skid (Eckholm, Fast M10, Holz, Timbersled, Fabcraft) to get the ride that I want. I've been waiting 2-years for the aftermarket, Works Performance or similar, to come up with some sort of decent "direct replacement" shocks. I have seen nothing. I did see Holz has a summer special for their rear suspension kit. $1,000.00 for a coil-over rear skid setup with Fox zero-pros. Still kind of spendy when all I really wanted is one rear shock that actually works.

 

[HAMMER]

 

[HAMMER]

Talked to Ross at Hygear and throwing money at shocks for the Yamaha mountain suspension just isn't worth it. Gave up and ordered the Holz suspension for $1,000.00

Picture of Ripntear's Apex with the Holz installed: