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I don't know where to find taller shocksand forks for my xr75 my buddy is offering me a set of 1986 CR80 Forks and Triple Tree selling them for 65 bucks and was wondering if a set of KDX 80 forks and Triple Tree would fit my 1978 xr75

And I was wondering where I could find a 1983 xr100 swing arm I checked eBay and can't find any if there is a different swing arm that is longer than the stock xr75 swingarm that will fit other than a Z50 swing arm

Picture below shows my xr75 in its current state the shocks you see on it are just there for height they are currently too stiff
 

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... I was wondering where I could find a 1983 xr100 swing arm ...
I am not able to point you to a currently available swing arm for a 1983 XR100, but am posting to encourage you to broaden your search to include additional model years.

The '84 XR100 uses the same identical swing arm as the '83, right down to the paint code (52000KA8000ZC *r119*).

The '81 & '82 use a similar arm that MAY only differ from the '83/'84 in that the paint code is different 52000KA8000ZB *r23*).

In case you haven't already been advised, the XR100 brake arm is likely longer than the OEM arm on the XR75.

I seem to recall that the diameter (possibly length, too) of the swing arm bolt differs from that of the XR75. If so, parts and modifications will be required to complete the swap.

Can't speak to the adaptability of the CR80 front end or the Kawasaki fr/rr parts. One aspect about the Kawasaki rear shocks is whether they utilize the same mounting brackets or something different that will require frame/arm mods.
 

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I don't know where to find taller shocks and forks for my 1978 XR75 ...

And I was wondering where I could find a 1983 XR100 swing arm ...
I realize the OP has not been on line for nearly a month. Just the same, perhaps the following may help someone else.

The fr/rr suspension from an '83 XR100 (or equivalent) parts bike appears to offer a LOT of compatibility w/ a '78 XR75. The advantage of finding a parts bike is that the more complete it is, the fewer the odds-'n-ends you need to hunt down individually (brake arm, front brake cable, axle ...).

Some rough measurements from an '83 XR100 and an '82 XR80 - taken in unfavorable conditions and subject to verification:

Front

  • Fork stanchion tube dia: 27mm (1.063") on both bikes
  • Fork length - top of tube to axle C/L: 710mm (XR100 w/ leading axle) vs 630mm (XR80 w/ bottom mount axle)
  • Head tube length: 160mm on both
Rear

  • Swing arm length
    • Overall: 475mm (XR100) vs 405mm (XR80)
    • Pivot bolt C/L to axle C/L: 420mm vs 355mm
    • Pivot bolt C/L to lower shock mount C/L: 325mm vs 323mm
    • Pivot gap beween L/R bushings: 110mm
  • Swing arm pivot bolt
    • thread OD: 0.405" (XR100) vs 0.389" (XR80)
    • Bolt, swing arm pivot: 90121-KA8-000 (XR100) vs 90121-063-000 (XR80)
    • Nut, self lock: 90304-GA6-003 (XR100) vs 90351-268-000 (XR80)
    • Bushing, swing arm pivot: 52181-001-300 for both bikes
Although the pivot bolt thread OD is different and the pivot bolt P/Ns are different between the XR100/XR80, the diameter of the pivot BOLT SHANK may be the same because both bikes use the SAME swing arm PIVOT BUSHING.

At some future date, I might post again after I have an opportunity to remove pivot bolts from the two models for a side by side comparison.
 

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Currently I am modifying the triple clamps of a kx65 to fit on a sl70 frame. I don't know the specs for the stem of the clamps in comparison to the xr75 but that could be an option for you.
 

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Currently I am modifying the triple clamps of a kx65 to fit on a sl70 frame. I don't know the specs for the stem of the clamps in comparison to the xr75 ...
I can't speak for the OP, but after looking at the specs and images of the 2017/18 KX65 I am interested in knowing more (the KX65's 33mm leading axle conventional forks with 8.3 in travel and 4-way rebound damping caught my attention.)

My XR triple clamps are presently assembled to their respective frames and I've never had the inclination to take measurements. So I can not offer actual XR dimensions.

However, my '77 & '78 XL clamps are on the bench & available for measurements.

While the castings for the XR/XL lower triple tree differ from one another mainly because the XL includes a mounting tab for the steering lock, I believe in other respects they are similar. I KNOW that both XR & XL 75s use the same P/N #53212-030-010 for the "RACE, STEERING CONE (LOWER)". So here are some ROUGH measurements from my XL75 lower triple clamp:

'77 & '78 XL75 Triple Clamp

  • Stem OD: 23mm
  • Race, Steering Cone (Lower) OD: 38mm
  • Stem length, Overall (from triple casting to end of stem): 198mm
  • Stem length, From triple casting to beginning of thread for Steering Head Top Nut: 163mm
air50, are there any other XR/XL75 dimensions you need in order to respond ?
 

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Heres a print I made for my stem I want to make. The 15mm is what gets pressed into the lower clamp. I may change it I still need to figure out how thick the KX top clamp is compared to the SL and add it on there.
View attachment Stem.PDF
 

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the top of the stem needs to be 15mm longer and depending on your races and bearing setup that will need to be changed from my drawing I actually had some stuff wrong on that drawing i will post an updated one later this week.
 

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I don’t know budget, but the aluminum swingarm from xr mini is a direct bolt on and looks great, and in my 83 xr80, i was able to put on front forks off an 2003 xr100. Back shock I got out of junk yard, thought to be from Elsinore, had to change rubber bushings between sock shocks and these
 

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tbh, your XR80 resto mod turned out REALLY well.

The swingarm from XR Mini and those '03 XR100 forks compliment each other very well. Nice score finding shocks at a wrecker's that bolted in w/ just a bushing swap.

The Maier side panels look great. Are the f/r fenders from Maier, too; or OEM?
 
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