KZ 650 GSXR 750 front end swap
- perattzi
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KZ 650 GSXR 750 front end swap
05 Nov 2008 20:54
I am starting a 1978 KZ650 cafe racer project this winter. So far the biggest progress has been the front end swap, I chose a front end off a 2001 GSXR750. After trying to make the stock gixxer stem work I opted to swap the steering stems...first I grinded the weld off the bottom of the lower triple. The stem then tapped out easily. From there I took the pieces to a machinist where he pressed out the stem from the lower GSXR triple, then a type of sleeve was made that copied the GSXR stems stepped design then welded to the kz650 stem and pressed into the GSXR triple.
Then the opening in the GSXR upper triple had to be machined larger to accept the KZ stem. We opted to bore it a little larger than needed and need fabricate a metal press fit sleeve. Now the stem is secured in metal instead of aluminum. However, the only issue is that the kz stem does not line up flush with the upper triple. I thought about milling material off the bottom to close the gap, but there is not enough material there. Heres what I mean about the gap.
I am not sure if this is an issue or not...I am thinking it will be fine because the nut under the triple seems to do most of the securing and besides the bolt on top engages most of the threads anyhow. What do you guys think?
Here it is bolted up.
Then the opening in the GSXR upper triple had to be machined larger to accept the KZ stem. We opted to bore it a little larger than needed and need fabricate a metal press fit sleeve. Now the stem is secured in metal instead of aluminum. However, the only issue is that the kz stem does not line up flush with the upper triple. I thought about milling material off the bottom to close the gap, but there is not enough material there. Heres what I mean about the gap.
I am not sure if this is an issue or not...I am thinking it will be fine because the nut under the triple seems to do most of the securing and besides the bolt on top engages most of the threads anyhow. What do you guys think?
Here it is bolted up.
1978 KZ650B w/ Zuki running gear project
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- perattzi
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Re: KZ 650 GSXR 750 front end swap
05 Nov 2008 20:59
1978 KZ650B w/ Zuki running gear project
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- donthekawguy
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Re: KZ 650 GSXR 750 front end swap
06 Nov 2008 00:05
You might want to use a longer bolt. Do you remember if the hole was flush with the top triple on the stock set up? If it was or even close you could measure how far down the threads are and find a longer bolt. You may have to cut it off or use a spacer but having more threads holding a critical part on is better than having to worry about it whenever you ride.
Rathdrum Idaho
1971 Kawasaki g3ss
1972 Yamaha R5 350
1965 Suzuki Hillbilly
1964 Yamaha 125
1971 Kawasaki g3ss
1972 Yamaha R5 350
1965 Suzuki Hillbilly
1964 Yamaha 125
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- Old Man Rock
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Re: KZ 650 GSXR 750 front end swap
06 Nov 2008 01:57
Hard to see in the images but it seems the top triple is not down all the way onto the bearing raceway... Maybe just deceiving.
If you where to loosen the top fork clamps, will the top triple go down further (rubber mallet)?
OMR
If you where to loosen the top fork clamps, will the top triple go down further (rubber mallet)?
OMR
1976 KZ900-A4
MTC 1075cc.
Camshafts: Kawi GPZ-1100 .375 lift
Head: P&P via Larry Cavanaugh
ZX636 suspension
MIKUNI, RS-34'S...
Kerker 4-1, 1.5" comp baffle.
Dyna-S E.I.
Earls 10 row Oil Cooler
Acewell 2802 Series Speedo/Tach
Innovate LC1 Wideband 02 AFR meter
Phoenix, Az
MTC 1075cc.
Camshafts: Kawi GPZ-1100 .375 lift
Head: P&P via Larry Cavanaugh
ZX636 suspension
MIKUNI, RS-34'S...
Kerker 4-1, 1.5" comp baffle.
Dyna-S E.I.
Earls 10 row Oil Cooler
Acewell 2802 Series Speedo/Tach
Innovate LC1 Wideband 02 AFR meter
Phoenix, Az
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- perattzi
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Re: KZ 650 GSXR 750 front end swap
06 Nov 2008 19:38
Good idea Don, I should see how the original one lined up. Old man, the upper triple is resting on the nut that secures the stem. Thanks alot for the write up on how you did yours it helped me out a ton.
1978 KZ650B w/ Zuki running gear project
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- Mark Wing
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Re: KZ 650 GSXR 750 front end swap
06 Nov 2008 23:18
Looks good so far. I see your tank is still not painted, you may want to dent it in the front for fork clearance then smooth it out with some filler. I wish I did on my 650 with a ZX7 front forks.
Jesus loves you Everyone else thinks your an ***
77 KZ650 C1 with ZX7 forks, GPZ mono rear, wider 18 police wheels and Yoshimura motor.
Yorba Linda Cal.
77 KZ650 C1 with ZX7 forks, GPZ mono rear, wider 18 police wheels and Yoshimura motor.
Yorba Linda Cal.
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- rstnick
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Re: KZ 650 GSXR 750 front end swap
07 Nov 2008 15:29 - 07 Nov 2008 15:32
Keep the progress pix coming. 
My buddy Drew's bike showing how he had his dented:
There's a write up on some of his build here:
dotheton.com/index.php?topic=2735.0
Mark, your bike was mentioned in the above post as well.
.
to dent it in the front for fork clearance
My buddy Drew's bike showing how he had his dented:
There's a write up on some of his build here:
dotheton.com/index.php?topic=2735.0
Mark, your bike was mentioned in the above post as well.
.
Rob
CANADA
Need a key for your Kawasaki? PM me
1978 KZ650 C2, 130K kms, Delkevic ex, EI, CVK32, PMC easy clutch, ATK fork brace, steering damper, braced swingarm, ZRX shocks, 18" Z1R front wheel.
2000 ZRX1100
2011 Ninja 250R - Wife's
2005 z750s
1978 KZ1000 project
1983 KZ1000R2 Project
CANADA
Need a key for your Kawasaki? PM me
1978 KZ650 C2, 130K kms, Delkevic ex, EI, CVK32, PMC easy clutch, ATK fork brace, steering damper, braced swingarm, ZRX shocks, 18" Z1R front wheel.
2000 ZRX1100
2011 Ninja 250R - Wife's
2005 z750s
1978 KZ1000 project
1983 KZ1000R2 Project
Last edit: 07 Nov 2008 15:32 by rstnick.
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Re: KZ 650 GSXR 750 front end swap
07 Nov 2008 15:29
Rob
CANADA
Need a key for your Kawasaki? PM me
1978 KZ650 C2, 130K kms, Delkevic ex, EI, CVK32, PMC easy clutch, ATK fork brace, steering damper, braced swingarm, ZRX shocks, 18" Z1R front wheel.
2000 ZRX1100
2011 Ninja 250R - Wife's
2005 z750s
1978 KZ1000 project
1983 KZ1000R2 Project
CANADA
Need a key for your Kawasaki? PM me
1978 KZ650 C2, 130K kms, Delkevic ex, EI, CVK32, PMC easy clutch, ATK fork brace, steering damper, braced swingarm, ZRX shocks, 18" Z1R front wheel.
2000 ZRX1100
2011 Ninja 250R - Wife's
2005 z750s
1978 KZ1000 project
1983 KZ1000R2 Project
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