Advice on YZF450 Rear Shock.....

[Blaster68]

Hey guys...can anyone tell me exactly what i will need to replace my stock 05 Blasty rear shock with a YFZ450 Rear shock...i mean besides the shock itself? Does it require a different bushing or some kind of retro fit or modification? Also, what can i expect to pay for a decent 450 shock?

Thanks
Stephen..:-/

 

[Teflon]

You'll have better luck fitting a 400EX rear shock in there.

The YFZ one is too long and will jack up the back of the bike too much. Only way to correct this is too shorten the shock itself. I think Pickled Beats did something like that on his build...

For the 400EX, you just need some bushes made up for the top mounting and drill out the bottom mount to accept the bigger bolt. Watch Ken O' Connors youtube video for tips...

 

[Blaster68]

Thanks Teflon...Appreciate the advice and the tips..

 

[Blaner]

something you may want to try on the 400ex is a bush at the bottom mount too. Ken Oconner doesnt use on in his vids but Teflon and I have found that without one, there is the risk of over tightening the bolt which can cause the shock alloy to bend and also the shock needs to pivot there to some degree.

As you can see in the pic, I had a brass bush made to fit tightly through the shock (15mm OD, 10mm ID) it fits exactly through the shock mount and is flush on either end. This prevent over tightening and possible collapse of the "wings". Also, in the case of wear between the bolt and the shock, the brass bush will wear which i can then replace, whereas without it, the shock alloy would wear and that damage is not repaireable!

 

[blasterdemon7]

As far as I know, the TRX shock is the same eye to eye as the 400ex. The res is offset so you will have to remove one body mount tab. I've read that some people think it rides a little better then the 400ex shock.

 

[blasterdemon7]

something you may want to try on the 400ex is a bush at the bottom mount too. Ken Oconner doesnt use on in his vids but Teflon and I have found that without one, there is the risk of over tightening the bolt which can cause the shock alloy to bend and also the shock needs to pivot there to some degree.

As you can see in the pic, I had a brass bush made to fit tightly through the shock (15mm OD, 10mm ID) it fits exactly through the shock mount and is flush on either end. This prevent over tightening and possible collapse of the "wings". Also, in the case of wear between the bolt and the shock, the brass bush will wear which i can then replace, whereas without it, the shock alloy would wear and that damage is not repaireable!

I always like a bush at the bottom mount.

 

[blasterdemon7]

I don't see the point in the bottom mount to protect for over tightening . The bottom bolt of you use one and not the pin, should only be just snug with loctite on it. If the bottom hole wears out, it can be filled in some with aluminum welding and re drilled.

 

[Blaner]

yes, but not everybody will know when to stop with the spanners... I use nylock nuts so I dont have to make it tight and yet keep the nut on. The main idea of the bush is to absorb wear. No, its not mandatory and I ran for about 2 years without one but wear was developing and so I felt this was the most correct solution

 

[Austyn249]

You'll have better luck fitting a 400EX rear shock in there.

The YFZ one is too long and will jack up the back of the bike too much. Only way to correct this is too shorten the shock itself. I think Pickled Beats did something like that on his build...

For the 400EX, you just need some bushes made up for the top mounting and drill out the bottom mount to accept the bigger bolt. Watch Ken O' Connors youtube video for tips...

Well I put the yzf450 rear shock on mine but u would have to really adjust the sag on it buy I personally like it, oh and u need the Ken oconner kit

 

[Paulie B]

I ran a YFZ450 shock on my Blasty. You will need a tapered bolt similar to what KOR sells for other shock conversions.
You will have to cut the shock down on the bottom and re-drill the mounting hole- this makes no difference in how the shock works and will lower the back end alot.
Finally in my opinion it will be still too stiff for a stock swinger. This kind of swap will def favor a longer swingarm.

 

[mud runner]

you will have to move the shock mount back on the swing arm

 

[Paulie B]

you will have to move the shock mount back on the swing arm

negative .

 

[JonS]

how long eye to eye is a yfz rear shock? just for my own info.

 

[Teflon]

how long eye to eye is a yfz rear shock? just for my own info.

Last I recall it was 18.5" for the 04-05 models and 18.75" for 06 up models

 

[JonS]

Last I recall it was 18.5" for the 04-05 models and 18.75" for 06 up models

so, lets say i had a +4 extended swinger with the mount moved back 1". that would work pretty well with a yfz shock and only make the bike sit up a little higher than stock right?