HopFrog's 1980 KDX175 Build Log

Discussion specific to the various air-cooled KDX models sold in the USA
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HopFrog175
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »


I got ahold of the KX80/85 clutch cushions and tried them out. The outer diameter is fine but the inner "D" is too large with a lot of slop. Digging through the junk box I found some vinyl tubing just about the right size. With a little heating I got it over the "D" post on the hub and trimmed it flush.


Clutch cushion shim
_click image to zoom_
kdx175_01_kdx175_clutch_cushion_shim.jpg
kdx175_01_kdx175_clutch_cushion_shim.jpg (263.86 KiB) Viewed 2144 times


The fit came out great!


Fitted clutch cushion
kdx175_02_fitted_clutch_cushion.jpg
kdx175_02_fitted_clutch_cushion.jpg (326.91 KiB) Viewed 2144 times


Next, the thickness of the KX80 version is too great so I tried a few ways to shave off a bit. Grinding seemed like a nice square method but the rubber kept flexing and came out anything but square.


Rubber grinding
kdx175_03_rubber_grinding.jpg
kdx175_03_rubber_grinding.jpg (293.11 KiB) Viewed 2144 times


So back to the basic razor blade. I used the 6-holed disk from the clutch hob to hold the rubber cushion while cutting and to set height at which to cut. The first one is chewed up a little from grinding but should be fine. Five more to go and then I can decide on rivets or machine screws for assembly.


Trimming to height
kdx175_04_rubber_trimming.jpg
kdx175_04_rubber_trimming.jpg (202.4 KiB) Viewed 2144 times

hf175w.jpg
hf175w.jpg (5.94 KiB) Viewed 2144 times
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Re: HopFrog's 1980 KDX175 Build Log

Post by KDXGarage »

Man! Good job on working out a solution.
Thank you for participating on kdxrider.net. :bravo:
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Re: HopFrog's 1980 KDX175 Build Log

Post by kaiser »

hey mate great job!
i just pulled a kdx175 motor down mine has very thin shims between the crank and bearing, i couldnt see this in you photos, i had a look at parts diagram and unable to see these shims. just cuirous thanks!
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Re: HopFrog's 1980 KDX175 Build Log

Post by KDXGarage »

kaiser, can you post some pictures? That does not sound correct (as delivered when new)

Check my signature on how to post pics.
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Re: HopFrog's 1980 KDX175 Build Log

Post by kaiser »

Yea I thought it was odd as well. Here is a pic same on both sides.
PXL_20210918_081823325.jpg
PXL_20210918_081823325.jpg (3.69 MiB) Viewed 1093 times
Thanks
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »


Hi Kaiser, Here are some additional pictures of my crank. I do not remember any shims between the bearing / web - I definitely do not remember two shims. And, I don't think I see any in the pics or layout. I am pretty darn sure I had no such shims.


No crank shims
_click image to zoom_
kdx175_1_crank.jpg
kdx175_1_crank.jpg (313.15 KiB) Viewed 1046 times
kdx175_2_crank.jpg
kdx175_2_crank.jpg (255.21 KiB) Viewed 1046 times
kdx175_3_crank.jpg
kdx175_3_crank.jpg (147.36 KiB) Viewed 1046 times
kdx175_4_crank.jpg
kdx175_4_crank.jpg (163.58 KiB) Viewed 1046 times
kdx175_5_crank.jpg
kdx175_5_crank.jpg (122.36 KiB) Viewed 1046 times


The shims in your pics look thick enough to tell if things are binding up on reassembly. I would be surprised if the factory tolerances were that loose - but, maybe. Or, maybe some work was done (to clean up some damage?) that took off some metal somewhere.

If it were mine, I would do a test assembly without the shims and use a press to see if I could move the crank (wedging the crank with a chisel placed opposite the rod of course). A dial indicator or dial caliper would probably work if there was a good reference surface.

Or, I would just assemble it cautiously and check for binding by hand and watch for a small gap between the cases (mine had no gap after pressing together).

---

Actually, come to think of it, I am glad you wrote - my motor has been apart by a previous owner who performed some slip-shod work - my motor could just as easily be missing shims! I just finished the clutch hub (riveted, post coming) and will be putting the motor back together next. I will definitely check crank clearance.

Let us know how it goes and feel free to post again - I am interested to hear of you progress!
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Re: HopFrog's 1980 KDX175 Build Log

Post by Molly's 70 »

I have seen washers on both sides of the connecting rod. Like thrust washers. Other Kawasaki 175's had them. I wonder?
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Re: HopFrog's 1980 KDX175 Build Log

Post by kaiser »

so i assembled without the shims, found i could push the crank side to side by about .25mm have decided to pull down my other kdx175 to look and no shims,
I have split the cases again and will put the shims in and see how it all goes.
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »


Thanks for the update Kaiser. I will measure my crank side-play this weekend and feel better after hearing one engine had no shims!
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »


Back on my clutch with new rubber cushions - screws or rivets? I had a friendly back and forth with the local rivet place (Hanson Rivet) and they sent out their closest match. They were a little bit under on the diameter but seemed close enough.

My alternative would be to tap and use machine screws with loctite (which is not uncommon on replacement kits for clutch cushions and hubs).

It seemed like either method would be ok so I flipped a coin and went with the rivets.


Clutch hub riveting
_click here to zoom_
kdx175_clutch_rivet.jpg
kdx175_clutch_rivet.jpg (259.89 KiB) Viewed 702 times
_click here to zoom_
kdx175_clutch_rivet2.jpg
kdx175_clutch_rivet2.jpg (189.69 KiB) Viewed 702 times
_click here to zoom_
kdx175_clutch_rivet3.jpg
kdx175_clutch_rivet3.jpg (267.81 KiB) Viewed 702 times


It did not take that long to hammer 'em down, some came better than others but, overall, I am quite happy with the result - one less thing to worry about coming apart :grin:

(Details and part numbers will be in a later post.)


hf175w.jpg
hf175w.jpg (5.94 KiB) Viewed 702 times
HopFrog175
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »

KDX175 Clutch Hub Rubber Cushion and Rivet Details

The clutch hub replacement cushion seems to be unavailable for the KDX175. The closest match that I could find is the KX80/85/100 '88-20. It is slightly larger than the KDX175 cushion and needs to be shimmed for a snug fit on the "D" post. The cushion also needs to be sliced slightly thinner to fit (see a few posts back for details).

The rivets are not listed by the parts suppliers and, presumably, are not available from Kawasaki. Working with a local rivet place, I used a close match to great success.

Part numbers and sources follow. See a few posts back for dis-assembly / assembly details and photos.


Quick list
Sep 30, 2021


OEM KDX175 cushions
kdx175_01_cushion.jpg
kdx175_01_cushion.jpg (66.52 KiB) Viewed 578 times
Closest replacement KX80/85/100 '88-20 cushions
kx80_02_cushion.jpg
kx80_02_cushion.jpg (93.05 KiB) Viewed 578 times
Rivet diagram
kdx175_03_rivet.jpg
kdx175_03_rivet.jpg (105.99 KiB) Viewed 578 times
Replacement rivet - allow 0.156" Clinch Allowance for total length of 0.621"
kdx175_04_rivet.jpg
kdx175_04_rivet.jpg (167.08 KiB) Viewed 578 times
Rubber cushions (dampers)

Pro-X seems to be the manufacturer/importer of the rubber clutch cushions which are
 available from several resellers.

Clutch cushion Manufacturer

Pro-X Part number   Description  
-----------------   -----------------------------------------
17.CRS4198-6        ProX Clutch Rubber Set KX80/85/100 '88-20 

https://www.pro-x.com/search/?search-brand=2&search-model=245&search-year=2003&search-submit=SHOW+RESULTS
 - scroll down to "Clutch Cushions


Clutch cushion sources

SVS Powersports Part number               Description                     Price
---------------------------   ----------------------------------   ------------------
           115817             PROX CLUTCH RUBBER SET KX85 '01-18   $38 for a set of 6
https://www.svspowersports.com/
 - clutch cushions may not be listed online - a call may be needed to order

-----

  Parts Giant Part number                  Description                     Price
---------------------------   ----------------------------------   ------------------  
           383948              ProX Clutch Cushion Set KX85 '03    $36 for a set of 6
https://www.partsgiant.com/p383948-prox-clutch-cushion-set?f=126306

-----

    Amazon Part number                  Description                     Price
---------------------------   ----------------------------------   ------------------
        B07HF5498Y            Pro-X 17.CRS4198-6 Clutch Rubbers    $35 for a set of 6
https://www.amazon.com/s?k=B07HF5498Y&ref=nb_sb_noss
 - SVS Powersports sold through Amazon

-----

Ebay is another possible source

--------------------------------------------

Rivets

Rivets are also unavailable from the usual motorcycle parts sources. The rivet place I went to had a close
 match that was fine. If you contact other rivet houses, however, you may find a rivet with a closer match
 of the diameter.

Rivet Manufacturer and Supplier

Hanson Rivet part Number  Description
-----------------------   ------------------------------------------------------------
   Countersunk Head       Steel rivet, countersunk head, 5/32" diameter, 0.621" length

https://www.hansonrivet.com/rivets/solid-rivets/commercial-solid-rivets/
 - call to inquire
 - ask nicely and a sample of 10 rivets cut to length may be forthcoming :-)
 - the OEM rivet has a diameter of about 0.167"
 - the new rivet has a diameter of about 0.156"

--------------------------------------------

Rubber Cushion Shim

   Generic Supplier                        Description
-----------------------    ----------------------------------------------------------------------
     Vinyl tubing          Black semi-rigid vinyl tubing, approx 0.590" OD, 0.075" wall thickness

 - as described in the earlier post, heat the end of the tubing and fit it over the "D" shaped post.
 - trim flush with the top of the post
 - the new KX85 clutch cushion will now fit snugly



The end result is a bit stiffer as the new clutch cushions are slightly larger in OD - it takes a little bit of coaxing to assemble.

That's it :grin:
Last edited by HopFrog175 on 12:17 am Oct 02 2021, edited 1 time in total.
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Re: HopFrog's 1980 KDX175 Build Log

Post by Goofaroo »

You’re making me feel like a slacker. lol

It’s not easy and very time consuming to document your work in such detail. You’re doing a very thorough job of bringing this 175 back to it’s original glory. Anyone following in your footsteps will certainly benefit from your hard work.

Keep up the good work and don’t think it is going unnoticed. I’m sure there are quite a few of us that will be following along until completion. Thanks for letting us tag along.
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »

Thanks Goofaroo, the people and posts on this site have been a great help. Hopefully I can add a little bit to it!
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Re: HopFrog's 1980 KDX175 Build Log

Post by bazwalton »

Hi HopFrog, Fantastic thread. Many thanks for the heads up on swinging arm sleeves. I am still riding and racing 175s weekly and was about to go down the making hardened steel sleeves as they are getting thin on the ground.
I have far too many 175s so awhile ago I looked about for replacements via bearing suppliers for the hard to find ones. The outer unitrack bearings are readily available from suppliers along with swinging arm bearings. The threaded rose joints are also easy to get. There isn't much point in me listing the suppliers as I'm in the UK.
The only one that is a bit of a dog to find at a reasonable cost is the centre of the uni arm. In the end I opened out the arm and used a different bearing. (I think there is still a post about it on my fb page, Classic Mann https://www.facebook.com/Vintagekdx )
If you decide to lighten the bike with ally the 81 kx 125 swinging arm is the one to find. Also the unitrak arm is a lot of weight high up so switching to an ally version is all goodness.
I wish I had read you thread as you were posting about the grease nipples (UK term for zerks) as I looked into this a few years ago and realised the same thing, no clearance for the grease. ( I was literally mouthing at the monitor, don't drill it, don't drill it. )
On the upside the great thing about the 175s is that stripping them down and regreasing everything is so easy and fast that 'after every race' is a pleasure not a chore.
And finally, well done on the chronicling of each part of the rebuild in such detail. I have a whole tips and builds section on my page and I wish I had a pound (dollar) for every time I finish doing something, look over at the unsed camera on the side and think.. 'Bo***cks'. Hahaha.
Cheers
Baz
https://www.facebook.com/Classic-Mann-952895831458690/ Kdx racing and restoration.

Kdx175x5 Kdx200x4 Kdx220x2 Kdx450. Kdx200AF.
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Re: HopFrog's 1980 KDX175 Build Log

Post by HopFrog175 »


Hi Baz, thanks for writing in! It's good to hear you reached similar conclusions on suspension joints, grease nipples, etc. (Btw, I would welcome info on any additional suppliers, even in Europe -in fact, I got my Timken bearings from the UK and prices/shipping times were fine, under a week to get here).

Thanks for the swing arm tips, I figure I may go down that route once the shock gives out - I have no idea how long it will last.

I am looking through your facebook now, it is nice to find another treasure trove of kdx-ness!

Best,
Hopfrog175
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