cr125 with one-off parts

xrta-stark
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3/19/2023
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fårholm, FI
Edited Date/Time 4/22/2023 3:49am

So I picked up this cr125 and decided to make the bike fresh for next riding season. 

I'm going for a full rebuild: + I'm going to machine some one off parts like triple clamps, linkage, cylinder head etc. Im especially sharing some pics of these cnc parts.

​​​​Also swapping a '99 cylinder and doing a long rod conversion ( like Michael Byrne's 2003 cr125 ) 

b455fd842ea129d0-medium

 

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xrta-stark
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3/19/2023
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fårholm, FI
3/23/2023 5:00pm

I already started tearing it down a few weeks ago. Glad there were no suprises.

The first fun little project was to design and machine new triple clamps. I dont like the cast aluminum clamps so I spent few nights drawing a new 3d cad model. IMG 20230323 115941561 HDR~2

 These clamps are stronger in critical spots, but also a few grams lighter than stock. Fem analysis was also made.

6
xrta-stark
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fårholm, FI
3/23/2023 5:05pm

IMG 20220813 220510924 HDR~2

 Lower and upper first op.IMG 20220814 155636441~2.jpg?VersionId=chU8hBmxE681XjocfP6BCmhDig

 

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xrta-stark
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fårholm, FI
3/23/2023 5:06pm Edited Date/Time 3/23/2023 5:12pm

IMG 20221016 143302854 HDR.jpg?VersionId=Qh5Am2eOpjet2mn5R84ZfLKTF5z4d

 Done. I'm also sending these clamps to anodizing 

21
Glen
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Rockaway, NJ, USA
3/23/2023 5:16pm

beautiful work!

2

The Shop

xrta-stark
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fårholm, FI
3/23/2023 5:33pm

IMG 20220621 171810785 HDR~2.jpg?VersionId=uTL.rSzdVYMIL.vCE1G

 

IMG 20220621 183351663 HDR~2 1

 7075 linkage arm with adjustable lenght. Similar to Luxon mx design.

12
3/23/2023 8:07pm

Amazing work. What model mill are you using?

3/25/2023 11:17am

Bad ass. Any idea how they will feel compared to stock clamps regarding rigidity?

Luxon MX
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San Diego, CA, USA
Fantasy
3/25/2023 12:17pm

Clamp topology looks familiar Wink

Nice job!

4
xrta-stark
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fårholm, FI
3/25/2023 1:06pm
Luxon MX wrote:
Clamp topology looks familiar  Nice job!

Clamp topology looks familiar Wink

Nice job!

Your clamps dont fit my bike so I had to make my own haha. I got some inspiration from your clamps but dont worry I only made one pair Smile  

 

IMG 20220708 004223786~2

 IMG 20221016 143130925 HDR

 here is the linkage

19
FarleyMX25
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Harrison, TN, USA
3/25/2023 5:10pm

Seriously impressive knowledge and ability being shown for this build. 

2
xrta-stark
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fårholm, FI
4/19/2023 1:22am

IMG 20230311 154159089 HDR 0.jpg?VersionId=aNQ2Lyf3n3

 parts came back from anodizing

9
xrta-stark
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fårholm, FI
4/19/2023 1:26am

IMG 20230311 160031621 HDR

new wheels

4
xrta-stark
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fårholm, FI
4/19/2023 10:06am

IMG 20230311 154607008 HDR

 IMG 20230311 154933243 HDR

 IMG 20221016 142241888 HDR

 cases cerakoted

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xrta-stark
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fårholm, FI
4/19/2023 10:15am

IMG 20221209 023921695 HDR

 Had to machine the crank so I can put balance inserts. It's was put together with longer rod so I had to calculate how much to remove weight.

 

IMG-20230219-WA0003

 air forks

6
Banana_oil
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Gothenburg, SE
4/19/2023 12:46pm

Wow, looks super! Will you use the 01 engine or a HPP?

xrta-stark
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fårholm, FI
4/19/2023 1:12pm
Banana_oil wrote:

Wow, looks super! Will you use the 01 engine or a HPP?

IMG 20230402 064724605 HDR

 hpp cylinder with spacer plate. The conrod is 6mm longer.

6
Wolfey
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Marquette Heights, IL, USA
4/22/2023 3:08am

Very nice ! Love the linkage!!

1
125mx.fi
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1/23/2012
Location
Vantaa, FI
4/23/2023 11:22am

What offset clamps did you make? 22, 24 or something else ?

Tumic
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Sundsvall, SE
4/23/2023 11:57am
xrta-stark wrote:
 hpp cylinder with spacer plate. The conrod is 6mm longer.

IMG 20230402 064724605 HDR

 hpp cylinder with spacer plate. The conrod is 6mm longer.

Did you use a ktm sx125 rod? 

sandman768
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Saratoga Springs, NY, USA
4/23/2023 12:26pm

In👍

xrta-stark
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3/19/2023
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fårholm, FI
4/24/2023 3:35am
xrta-stark wrote:
 hpp cylinder with spacer plate. The conrod is 6mm longer.

IMG 20230402 064724605 HDR

 hpp cylinder with spacer plate. The conrod is 6mm longer.

Tumic wrote:

Did you use a ktm sx125 rod? 

yes it's a ktm rod. 

xrta-stark
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fårholm, FI
4/24/2023 5:08am
125mx.fi wrote:

What offset clamps did you make? 22, 24 or something else ?

22

geeZ177
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Western NY area, NY, USA
4/25/2023 11:04am

Just incredible so far. Can't wait to see the final product!

125mx.fi
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1/23/2012
Location
Vantaa, FI
4/27/2023 12:13pm
125mx.fi wrote:

What offset clamps did you make? 22, 24 or something else ?

xrta-stark wrote:

22

Have you measured fork lug offset?  Lug offset in new forks can be 2mm less causing total offset change of 4mm.

Just a possibility that came into mind.

xrta-stark
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fårholm, FI
4/27/2023 12:43pm
125mx.fi wrote:

What offset clamps did you make? 22, 24 or something else ?

xrta-stark wrote:

22

125mx.fi wrote:
Have you measured fork lug offset?  Lug offset in new forks can be 2mm less causing total offset change of 4mm. Just a possibility that came...

Have you measured fork lug offset?  Lug offset in new forks can be 2mm less causing total offset change of 4mm.

Just a possibility that came into mind.

mitä luulet?

125mx.fi
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1/23/2012
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Vantaa, FI
4/28/2023 11:12am
xrta-stark wrote:

22

125mx.fi wrote:
Have you measured fork lug offset?  Lug offset in new forks can be 2mm less causing total offset change of 4mm. Just a possibility that came...

Have you measured fork lug offset?  Lug offset in new forks can be 2mm less causing total offset change of 4mm.

Just a possibility that came into mind.

xrta-stark wrote:

mitä luulet?

Of course you have measured. Absolutely brilliant build.

xrta-stark
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Joined
3/19/2023
Location
fårholm, FI
4/29/2023 2:38am

IMG 20230108 121028500 HDR 0

 IMG 20230311 154126253 HDR.jpg?VersionId=

 IMG 20221111 190141019 HDR.jpg?VersionId=v2h5G1FvEFaGzi.

 IMG 20230311 153713712 HDR.jpg?VersionId=aBYpMtNbaGeKtrE

 finally got the bottom end back together.

what do you guys think about the clutch cover

9
xrta-stark
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fårholm, FI
5/1/2023 5:25pm

IMG 20230323 120419494 HDR~2

 what's this 👀

DJV804
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Albertville, MN, USA
5/1/2023 8:41pm

If you wanted to make a few extra linkages, they would for sure sell!

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