Slingshot swingarm upgrade

[Hitman]

Good Day ALL

Has anyone fitted a k5 swingarm to and 88 750 slingshot frame. If so does anyone have any pics. 

 

[Donjuan]

1988 gsxr 850 frame

01-03 gsxr 600 swingarm 

98 gsxr wheel, brake and sprocket

you need a 520 chain because it’s tight against the frame. Also the swingarm axle is a smaller diameter so you can use  the bearing race  from the old swingarm.

You can weld or loctite the tighter for the correct fit and you’ll need an inside spacer for the smaller race.

Im still working on the suspension for the correct geometry but hopefully I’ll figure that out soon

[MeanBean49]

Ive put a k4 arm in a slingshot and a k5 arm in a HUC frame (same dimensions as slingy) just had to have top hat/bearing spacers machined up to make spacing correct and shrink the bolt hole size down to match slingy swingarm bolt. If your going to use a later wheel its worth noting that the sprocket offset is 10mm different to oil cooled wheels. Its a faff machining sprocket carriers, spacing front sprockets and running dished rear sprockets backwards to get the wheel central and the chain run correct. Otherwise you end up with either an out of centre wheel of the issue shown above.

With the k5 arm i used slingshot wheel and made new chain adjuster blocks that spaced down spindle size so i clild use slingshot wheel and spindle. Was loads easier

[MeanBean49]

Oh yeah. I used standard slingshot shock linkage and made adjustable dog bones to fit the later arms. Shock also needed re-springing due to the angle of dog bones changing and needing a different spring rate

[OX88]

18 hours ago, Donjuan said:

1988 gsxr 850 frame

01-03 gsxr 600 swingarm 

98 gsxr wheel, brake and sprocket

you need a 520 chain because it’s tight against the frame. Also the swingarm axle is a smaller diameter so you can use  the bearing race  from the old swingarm.

You can weld or loctite the tighter for the correct fit and you’ll need an inside spacer for the smaller race.

Im still working on the suspension for the correct geometry but hopefully I’ll figure that out soon

Is that a 5.5" rim or a 6"?

180 or 190 rubber? Just took delivery of a complete 01-03 swingarm myself, and want to fit it to my '88 gsxr750

[MeanBean49]

16 hours ago, OX88 said:

Is that a 5.5" rim or a 6"?

180 or 190 rubber? Just took delivery of a complete 01-03 swingarm myself, and want to fit it to my '88 gsxr750

6" rim wont really work. Unless you ignore the 10mm offset difference and have either the sprocket or wheel alignment wrong.

[Donjuan]

That is a 6.0 wheel and forgot to mention that I have a 90-92 motor in a 1988 frame.   The frames are different heights 88-89 and 90-92 and the sprocket shaft is longer on the later long stroke engines . I have never done a swingarm swap on an 88 frame and motor so what meanbean said sounds correct. I have run offset sprockets on other bikes for correct sprocket chain alignment.

 

[Donjuan]

The main problem is the different dogbone angles. Like meanbean said you need a softer spring or create the correct suspension geometry . 

 

Edited December 3, 2017 by Donjuan

[Donjuan]

Here are some pictures 

the last one is a pic of the dogbone angle from a 88 frame with stock suspension and 03 swingarm. The geometry is different from the early oil cooled frames so the shock spring is to stiff. 

Danm54 has created a suspension piece that should correct this problem. I haven’t finished my build yet and want the suspension to be correct for the track.

 Meanbean what spring rate are you running and have you had any problems?

[Donjuan]

Here’s some great pics

http://oldskoolsuzuki.info/forums/index.php?/topic/3561-gsxr-750-2003-swing-in-a-slingshot/

[MeanBean49]

Donjuan, what have you done to correct the 10mm difference in rear sprocket offset? 

[Donjuan]

Meanbean,

ill measure the shaft later today but I think the 90-92 engine has a longer sprocket shaft. The chain almost touches the 88 frame.

what spring rate did you run?

[MeanBean49]

Im not on about the shaft or anything engine side.

Iy you put a ruler from the centre of the wheel to the inside face of the rear sprocket. There about 10mm difference between oil cooled wheels and srad/k-series ones.

[Toddy64]

On 11/29/2017 at 7:37 AM, MeanBean49 said:

Ive put a k4 arm in a slingshot and a k5 arm in a HUC frame (same dimensions as slingy) just had to have top hat/bearing spacers machined up to make spacing correct and shrink the bolt hole size down to match slingy swingarm bolt. If your going to use a later wheel its worth noting that the sprocket offset is 10mm different to oil cooled wheels. Its a faff machining sprocket carriers, spacing front sprockets and running dished rear sprockets backwards to get the wheel central and the chain run correct. Otherwise you end up with either an out of centre wheel of the issue shown above.

With the k5 arm i used slingshot wheel and made new chain adjuster blocks that spaced down spindle size so i clild use slingshot wheel and spindle. Was loads easier

Hi Mean Bean / Gentlemen

Newbie to the group, but been running my 1100k for 20+ years.
Inspired by some of the stuff I see on here, so took the plunge and got a 750 K1 arm off Eblag for a bit of a winter project.

As I’m also using the original Slingshot wheel and spindle, i notice there is an 20mm gap using the standard spacers as the K1 arm is 20mm wider. I’m not sure how to align the wheel/sprockets, so wondered if you remember what spacers you used, I’m thinking 10mm each side looks about right, but really don’t know?

Thanks in advance

 

[MeanBean49]

43 minutes ago, Toddy64 said:

Hi Mean Bean / Gentlemen

Newbie to the group, but been running my 1100k for 20+ years.
Inspired by some of the stuff I see on here, so took the plunge and got a 750 K1 arm off Eblag for a bit of a winter project.

As I’m also using the original Slingshot wheel and spindle, i notice there is an 20mm gap using the standard spacers as the K1 arm is 20mm wider. I’m not sure how to align the wheel/sprockets, so wondered if you remember what spacers you used, I’m thinking 10mm each side looks about right, but really don’t know?

Thanks in advance

 

Im not 100% sure but iirc the disc side is the same distance from inside face of swingarm to wheel centre, so you just need 20mm thicker spacer on sprocket side.

[Toddy64]

Much appreciated Mean Bean, I apologise in advance as i may badger you again as the job unfolds. 

Similarly to yourself I’m working with the Slingshot Linkage and have an Ohlins shock (not sure if the length is adjustable mind) and it looks like the dog bones i will need are about 15 degrees off the horizontal, so not sure how that will work on the spring?

[MeanBean49]

9 hours ago, Toddy64 said:

Much appreciated Mean Bean, I apologise in advance as i may badger you again as the job unfolds. 

Similarly to yourself I’m working with the Slingshot Linkage and have an Ohlins shock (not sure if the length is adjustable mind) and it looks like the dog bones i will need are about 15 degrees off the horizontal, so not sure how that will work on the spring?

Its quite a while since i build my race bike, cant remember what spring rate i ended up with, did have to change it a couple of times to get it right.

Its also worth fitting everything with no shock spring fitted to shock. Lets you move it through the whole range of movement to make sure its all ok.

I raced mine for 2 years after getting it setup how i wanted with no problems at all

[Toddy64]

Thanks for that, i will indeed try without the spring. I raced a CBR600 way back in the 90s and remember too well the faff setting up suspension

Could you remember what 20mm rear spindle you used as the 1100K one is 315mm compared to the 28mm 750K1 item which is 330mm?

[MeanBean49]

1 hour ago, Toddy64 said:

Thanks for that, i will indeed try without the spring. I raced a CBR600 way back in the 90s and remember too well the faff setting up suspension

Could you remember what 20mm rear spindle you used as the 1100K one is 315mm compared to the 28mm 750K1 item which is 330mm?

Used k1 wheeks in my slingy so spindle wasnt an issue, may have been a zx6/zx9 one i used in HUC, couldnt be 100% though, i have many many random things in my lockup that im not exactly sure where they come from. I just usually manage to find what i need.

[ElVikingoTropical]

I cut of the link support from my OEM swing and welded it to the modern swingarm,

This way I keep the correct linkage and shocker.

[Toddy64]

On 11/29/2017 at 7:37 AM, MeanBean49 said:

Ive put a k4 arm in a slingshot and a k5 arm in a HUC frame (same dimensions as slingy) just had to have top hat/bearing spacers machined up to make spacing correct and shrink the bolt hole size down to match slingy swingarm bolt. If your going to use a later wheel its worth noting that the sprocket offset is 10mm different to oil cooled wheels. Its a faff machining sprocket carriers, spacing front sprockets and running dished rear sprockets backwards to get the wheel central and the chain run correct. Otherwise you end up with either an out of centre wheel of the issue shown above.

With the k5 arm i used slingshot wheel and made new chain adjuster blocks that spaced down spindle size so i clild use slingshot wheel and spindle. Was loads easier

Just got my K1 arm fitted into my 1100k and the suspension working, however as I’m using slingshot wheel, and with everything lined up correctly, the 530 chain rubs against the swingarm top centre brace? Any idea how to fettle this, as if I use a 5mm offset front sprocket, the rear would be out of line?

[TonyGee]

can you offset both sprockets ?  or use a none O ring chain. failing that grinding/cutting the brace !!!!!!! also converting the chain kit too 520 !!!

Edited December 19, 2020 by TonyGee

[Toddy64]

24 minutes ago, TonyGee said:

can you offset both sprockets ?  or use a none O ring chain. failing that grinding/cutting the brace !!!!!!! also converting the chain kit too 520 !!!

Other than using a K1 wheel etc, my only thoughts were 520 conversion and a 2mm washer behind front sprocket and similar behind the rear sprocket using five 2mm washers, but sounds a bit of a bodge? Was hoping someone may have already done it?

[Toddy64]

On 12/19/2020 at 3:03 PM, TonyGee said:

can you offset both sprockets ?  or use a none O ring chain. failing that grinding/cutting the brace !!!!!!! also converting the chain kit too 520 !!!

TonyGee, that is actually what I ended up doing, 520 non o ring chain, XR650 01-07 front sprocket with 5mm more offset than an 1100k one, and 5mm spacers behind rear sprocket. Not ridden yet but all seems to line up and more importantly clears the swingarm (bearing in mind a K1 wheel has the sprocket a further 10mm from centre than a Slingshot) so fingers crossed