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Discussion Starter · #1 ·
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i have a gixxer 750h slabside and i want a fatter rear wheel i have bought a 17 inch 5.5 inch wide wheel from a slingshot with a 190 tyre and it is hitting the chain also the brake caliper will not line up properly i keep seeing fighters with this rear wheel on but nobody will give me the time of day to say how to do it pleese help as im pulling my hair out now
 

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British Bloke in Canada
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190 on a 5.5 is large, go with a 180 allso tires very in size from difernt manufactures,
as for the brake caliper you would need the mount from the slingshot, for it to work, more than likely, though without a picture, eeek who knows.
 

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Discussion Starter · #3 ·
have i got the right wheel to use though it looks on pictures like people use the slingshot wheel or have i bought the wrong one
 

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Discussion Starter · #7 ·
its a slabby swing arm thats on i also have an 1100 slabby arm as a spare but it looks the same as the 750 one it fits the swingarm fine but its just the chain thats catching on the rubber of the tyre will a 180 tyre make a lot of difference clearence ways
 

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the mad doctor
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use the slingshot wheel, and the slabby spacers. i had a 190 on mine with no issues. make sure you have the right sprocket carrier. the slabby carrier is a different offset than the slingy's. you have to use the slabby rotor on the slingshot wheel too, with the slabby spacers.

the 750 and 1100 slabby arms are the same with the exception of the length.

sounds to me like you have the wrong sprocket carrier in that slingshot wheel though. they look similar, but like i said, the sprocket offsets are different.
 

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OLD GUY's RULE
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its a slabby swing arm thats on i also have an 1100 slabby arm as a spare but it looks the same as the 750 one it fits the swingarm fine but its just the chain thats catching on the rubber of the tyre will a 180 tyre make a lot of difference clearence ways
Op's , my bad. I ment to say you'll have to lose the slabby swingarm.
I rember seeing something about an R1 swingarm swap.
Think it was in old school suzuki...
Here it is minus pic's.....


R1 swingarm into GSX-R
by Lee Workman

ok here goes... ( i hope you appreciate this you bastards ! )

First thing is , to get the swingarm physically into the GSXR frame . NOTE ! - the R1 swingarm does not fit perfectly centrally in the R1 frame - it has an offset .

bolt the whole wheel , cush drive , caliper assy into the arm , and mark the centre position of the wheel - onto the swingarm pivot at the front .
you'll notice that it is offset - measure the width of your stock GSXR donor swingarm ( yes- you'll need one !) - transfer this measurement to your R1 swingarm , and chop off the excess ( from memory you'll end up removing about 35mm from one side and 25 from the other .

Now that you've chopped this material off , you no longer have a 'land' to accept the pivot bearings - this is handy because you can now 'bore' the virgin pivot tube out to accept stock GSXR bearings , and use your existing GSXR swingarm pivot spindle .

Now you should have the R1 swingarm in the GSXR frame .
You need to find the position of the linkage point , in relation to the pivot.



then you need to transfer these dimensions onto the r1 swingarm . once the pivot spot is marked each side - drill a hole - it should be in the 'box' section part of the r1 arm that surround the shock .

Cut out the 'horse shoe' shaped linkage mounting from the GSXR swingarm , dont take too much off the sides - you need to cut it as close to the 'spars' of the gsxr swingarm as possible - right through the weld .

there are a couple of flat plates welded to the underside of the swingarm - remove these and slide the GSXR linkage mounting into the space



Thread a long bolt ( i used a piece of M8 all-thread ) through the two holes you made in the R1 swingarm . the bolt should go through the GSXR 'horseshoe' . the bolt is what jigs the horseshoe linkage mounting into position .I made two 'stepped bushes' that fitted perfectly inside the bearings of the horseshoe - then i tapped them out to suit the all thread .

So can now thread the 'bolt' through an M8 nut >then through the 8mm hole in the swingarm bracing > M8 nut > stepped bush > linkage pivot < stepped bush< M8 nut < hole in the other side of the swingarm bracing < M8 nut .

see diagram below



now you can secure the 'all thread' bolt in position using the m8 locking nuts , either side of the 8mm holes that you carefully positioned and drilled into the R1 swingarm bracing . you can adjust the linkage mounting untill it is perfectly central and in line with the make that you made on the centre of the Pivot tube .

You will probably need to remove the 'horseshoe' and file a bit from the sides then re fit - several times - in order to get it a nice close fit , and positioned centrally .

Once in position - you just need to weld it up



the next job is to extend the oval hole in the top of the bracing forwards toward the pivot tube .

the reason for this is , the shock sits vertically in an R1 , but in a GSXR , the shock 'leans' forward - if you dont extend the hole in the bracing , the shock will foul it .

the last job is to open out one of the 8mm holes you made in the bracing - upto 18mm - this is so you can fit the bolt that secures the dogbones to the linkage pivot .



So now , if everything's gone to plan - your R1 swingarm is fitted centraly between the frame rails of your GSXR , Your GSXR pivot spindle slips through the frame , through the GSXR pivot bearings and out the other side , without any play

Your GSXR shock slips through the modified hole is the R1 swingarm , and your dog bones secure the linkage pivot to the rocker arm without any fuss .

if you've done it properly - you havent fucked up the geometry of the suspension , and there isn't any play anywhere .



One last thing -

I told you it was an absolute bastard didn't i ?

which is probably why i've never seen anyone else do this mod


yes it looks trick
yes it's unique
yes the ( extremely light ) R1 6" wheel plops straight in
yes the swingarm is actually lighter and (very much) stiffer than the old GSXR on it replaces
yes , all the original geometry , and linkage ratio's are retained

But would i do it again ?


Would i fuck !
 

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Discussion Starter · #12 ·
thanks for all the help guys im probably gonna try a 180 tyre i have the slingshot wheel with slabby spacers and spindle it just looks too close and with any flex in the chain when riding it would make it dangerous reacon it should be ok with 180 on
 

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GURU
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well 750H would be an 87 right? i had an rm250g that was an 86 so ill assume thats right. what did that thing have 4 or 4.5" 18" rim? well if your going to a wider rim your front and rear sprockets arent going to line up any more(unless for some reason your sprocket carrier on that thing put your chain close to the arm. sorry for this very horrible pic but here is what i did at first.
http://filebox.vt.edu/users/maperez/GPz/spr2.JPG

i took a flat sprocket, machined out the center section then used a piece of sch40 steel pipe to offset the sprocket 5/8". I tig welded the thing back together(in a lathe jig for most of it).

You can order offset sprockets for most bikes but mine didnt have one. I found an offset sprocket later and made a spacer to go behind it over the splines and thats what im currently running. Ive never dealed with slabby/slingshot combo so i dont know.
 

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Discussion Starter · #16 ·
thanks mate ive never considered that before it is an 86 with a 4.5 inch 18 ive never heard of this problem from other people who have converted but then i have never asked them about it
 
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