What years for a pre?

[Diggity]

I'm wondering what years of busa shocks fit in a pre 600?? Because I fitted a 08 on mine today and the chain won't leave the swing arm buffer with my 250 on it, all the settings are as soft as they go... --- I had to try it, I got it for $30 locally with 58 miles on it... Thanks

[Diggity]

Hopefully this pic will show you

[Black_peter]

Whoh.. Too long I guess.
I think the shock needs to stay around 11 inches..
Tmod?!?!?

[Tmod]

I am not a fan of Hayabusa shocks on the pre kats, IMO they are too long and add more problems then they solve. The 99-07 busa shocks are 340mm c to c and I prefer something right around 310mm. I tried a B12 shock on a 750 pre and didn't like they way it fit as you had to grind the lever and that is not a option to me. The B12 shock could be made to work by making a new spring retainer at the bottom with a step that raises that section so you won't need to grind the lever. I get the impression that some are trying to compensate for the wrong spring by raising the rear, If you weigh 250 then the spring is not even close to the correct one for you, So right now you have created a couple new problems by using that shock.

(1) Now the chain hits the pad all the time.

(2) You softened it up so much that the shock is not anywhere near where it should be set for your weight. If the spring is not right the damping cannot be correct as well.

EDIT: As a option you could always have that shock lowered internally to a shorter overall length.

Tmod

[Diggity]

Thats my thought too --- if you need pics let me know!!

[Diggity]

thats Tmod

[ctandc]

I tried a B12 shock on a 750 pre and didn't like they way it fit as you had to grind the lever and that is not a option to me. The B12 shock could be made to work by making a new spring retainer at the bottom with a step that raises that section so you won't need to grind the lever. I get the impression that some are trying to compensate for the wrong spring by raising the rear, If you weigh 250 then the spring is not even close to the correct one for you, So right now you have created a couple new problems by using that shock.

(1) Now the chain hits the pad all the time.

(2) You softened it up so much that the shock is not anywhere near where it should be set for your weight. If the spring is not right the damping cannot be correct as well.

EDIT: As a option you could always have that shock lowered internally to a shorter overall length.

Tmod

Okay...I read this last night, but was too tired to process it...

I have pre 600 with a B12 shock. I have nothing hitting at all. No mods needed no interference. The shock was a great improvement over the worn out ('91 Kat 600 with 28K at the time it was replaced) stock rear shock.

I'm assuming it's not hitting on a pre 600 because of the difference between the wheelbase lengths between the pre-600 and pre-750??

I haven't noticed any increased interference with the chain either. I've probably got close to 10K on that shock....what should I look for?

I'm 6'3" 240ish...and this raised the rear of the bike @ 2". It actually made the bike much more comfortable for me. It seemed to make intial turn in a lot less work as well. I left the front end alone except for PVC spacers / stock springs with new oil.

I honestly don't know what adjustment the B12 shock is on. I recently bought a spanner wrench so I can check / adjust if necessary.

I will admit the bike does ride stiffer in the rear. Before on bumps the rear of the bike just felt "soft" for lack of a better technical term. Now it's more firm....but I don't think overly so.

What do you recommend? Use this shock? But a post 750 shock and have it redone?

Thanks

[Diggity]

Honestly I was trying to stiffen the rear by just slapping in a new shock, I really didn't want to burden you (tmod) to make me up a custom shock...

[brentwoodkris]

Okay...I read this last night, but was too tired to process it...

I have pre 600 with a B12 shock. I have nothing hitting at all. No mods needed no interference. The shock was a great improvement over the worn out ('91 Kat 600 with 28K at the time it was replaced) stock rear shock.

I'm assuming it's not hitting on a pre 600 because of the difference between the wheelbase lengths between the pre-600 and pre-750??

I haven't noticed any increased interference with the chain either. I've probably got close to 10K on that shock....what should I look for?

I'm 6'3" 240ish...and this raised the rear of the bike @ 2". It actually made the bike much more comfortable for me. It seemed to make intial turn in a lot less work as well. I left the front end alone except for PVC spacers / stock springs with new oil.

I honestly don't know what adjustment the B12 shock is on. I recently bought a spanner wrench so I can check / adjust if necessary.

I will admit the bike does ride stiffer in the rear. Before on bumps the rear of the bike just felt "soft" for lack of a better technical term. Now it's more firm....but I don't think overly so.

What do you recommend? Use this shock? But a post 750 shock and have it redone?

Thanks

Same situation here. I've put about 1k miles on since my 05 B12 swap out on my pre600 with NO PROBLEMS. I have nothing but good things to say about it. The one thing I noticed is that when the bike is on its side stand, the chain now touches the pad, but as soon as I sit on it, its well clear of it again. Even more so when you ride 2-up for obvious reasons.

[Tmod]

Okay...I read this last night, but was too tired to process it...

I have pre 600 with a B12 shock. I have nothing hitting at all. No mods needed no interference. The shock was a great improvement over the worn out ('91 Kat 600 with 28K at the time it was replaced) stock rear shock.

I'm assuming it's not hitting on a pre 600 because of the difference between the wheelbase lengths between the pre-600 and pre-750??

I haven't noticed any increased interference with the chain either. I've probably got close to 10K on that shock....what should I look for?

I'm 6'3" 240ish...and this raised the rear of the bike @ 2". It actually made the bike much more comfortable for me. It seemed to make intial turn in a lot less work as well. I left the front end alone except for PVC spacers / stock springs with new oil.

I honestly don't know what adjustment the B12 shock is on. I recently bought a spanner wrench so I can check / adjust if necessary.

I will admit the bike does ride stiffer in the rear. Before on bumps the rear of the bike just felt "soft" for lack of a better technical term. Now it's more firm....but I don't think overly so.

What do you recommend? Use this shock? But a post 750 shock and have it redone?

Thanks

Hey ctandc,

Could you take a pic of from the side of the lower shock mount clevis and lever? As I stated I put a B12 shock on GSXFJim's bike and it did hit the lever. Yes he does have a 750 and if this happens on a 600 I don't know, Don't know anyone that has a 600 around me. Anyway the B12 spring is slightly stiffer than the stock pre spring so yes it would be stiffer as well as you now have a gas charged shock with different valving. My guess on the chain is that the B12 shock is 20mm shorter than a Hayabusa shock so you are no where near the height that the Hayabusa shock equipped bike would be. When I put the B12 shock on Jim's bike we didn't run into any chain issues either. It did raise the bike about 1.75" and I put a Hayabusa spring on his shock as the stock was not correct for his 240 lb weight. if you are happy with the height and the spring collar does not hit the lever than you are fine. IMO the spring is still not correct but if it feels better to you and you are happy then that is all that matters. Oh if you do take a pic and have the center stand please put it on the centerstand before taking the pic.

Thanks!!

Tmod

Honestly I was trying to stiffen the rear by just slapping in a new shock, I really didn't want to burden you (tmod) to make me up a custom shock...

Diggity,

I understand what you are trying to do and if I came across a little harsh I apologize, It was not intended to sound that way. Anyway there are many shops that will shorten the shock internally, By no means am I the only game out there. You could always sell that shock on Ebay and get a different one or live with what you have.

Tmod

[GSXFJim]

ctandc.. do you have any pics of your B12 installed.. the B12 in my '91 750 was a positive contact with the lower arm.. even with me sitting on it at 235lb. it was still touching. I dont think wheel base has anything to do with where the shock mount points are.
Tmod set me up with a 91 gsxr 1100 unit with a remote res. its 10mm shorter than the B12, it doesn't hit the bottom lever and is 10mm longer than the stock unit.. so far I'm happy with it.

[ctandc]

TMOD I'll try to take a pic this week.

So Tmod..what shock would you recommend for my size / weight?

How much would you charge to set up a shock for me?

Thanks.

[Diggity]

I took absolutely no offence to anything said... So I guess I have the same question as ctandc $

[Tmod]

TMOD I'll try to take a pic this week.

So Tmod..what shock would you recommend for my size / weight?

How much would you charge to set up a shock for me?

Thanks.

If the shock you have is not hitting then by all means stay with that shock as you seem to like it, The spring could be heavier for your weight and that alone will change the attitude of the bike, Could be the reason you don't mind the angle that you are sitting is due to it sitting lower than it should be due to the spring being the wrong rate for your weight. Usually springs go for right around $95.00 and then you would need a spacer as well. The spacer would be best at the bottom of the shock to gain more clearance between the lever and the spring or spring collar itself. The stock B12 spring rate is right around 10.7 kg/mm or 600 in/lbs and the spring I used for Hemi (250) was a 18.8 kg/mm or 1100 lbs/in rate. As you can see there is quite the difference between those two. When you get a chance to take that pic I would like to see it and then we can go from there.

I took absolutely no offence to anything said... So I guess I have the same question as ctandc $

If you have spent all that time to make the Hayabusa shock fit why not just shorten it? No need to get another shock or anything like that. I will Pm you a price on shortening it up for you and we can go from there.

Tmod

[Diggity]

that sounds like a plan Tmod -- seems how I made a new battery tray to work with that shock.