2002 HRC CR125R Fonseca with modern twist

mxav8r
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2/3/2026 8:14am

I vote the graphics with the Honda style wing.... and PLEASE more pictures and lay down some knowledge upon us! I know you have so much info about HRC. Would be cool just to read some cool behind the scenes info. Awesome build Matt!

matt.3150
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2/3/2026 9:45am Edited Date/Time 2/3/2026 10:02am
matt.3150 wrote:
Which shroud graphics you guys like better?Or

Which shroud graphics you guys like better?

IMG 0566 7.jpeg?VersionId=bMI


Or

IMG 0460 0.jpeg?VersionId=ld.mdmRf4vGYFfQeXOJn
If it was more of a Fonseca rep then I’d say the top ones, but as it has the modern twist i’d go with the bottom...

If it was more of a Fonseca rep then I’d say the top ones, but as it has the modern twist i’d go with the bottom. More pics please Matt!

Fonseca had the ones with the black Honda wing on his 250, along with MC. So ? I can go back and forth have both. 3 sets of plastic might do a full Fonseca plastic copy, with old HRC front number plate and the Cycra 05-06 number plate also and the white fork guards. Just looking at what others think. My the 04 black wing and Fonseca’s 250 is the 05 black wing but hard to really know unless your really really look into it. But he also had the 04 wing and the Old HRC number plate on his 04 RC250

Thanks 

IMG 0585 2
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JMX82
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2/4/2026 3:08am

There's just something super cool in those last-generation CR125s even though they weren't the fastest bikes out there at the time.  

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ohh_454
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Fantasy
2/12/2026 9:57am Edited Date/Time 2/12/2026 9:57am
matt.3150 wrote:
Which shroud graphics you guys like better?Or

Which shroud graphics you guys like better?

IMG 0566 7.jpeg?VersionId=bMI


Or

IMG 0460 0.jpeg?VersionId=ld.mdmRf4vGYFfQeXOJn

Top, all red looks cool

The Shop

matt.3150
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2/14/2026 8:52pm

Got my radiators


7639203277634011531 0592082621378437095 0

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matt.3150
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2/15/2026 11:50am

Here’s a little thing, more modern HRC air filter screw off a 4 stroke, modified to increase length for a 2 stroke! I like the little details.

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matt.3150
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2/16/2026 10:02am
matt.3150 wrote:
Got my radiators

Got my radiators


7639203277634011531 0592082621378437095 0

Lovely are they HRC?

Yes off a 05 rc250. 

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matt.3150
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matt.3150
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matt.3150
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matt.3150
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2/16/2026 6:43pm Edited Date/Time 2/16/2026 6:44pm

36mm bottom 38mm top

image 521

 

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matt.3150
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2/16/2026 6:46pm

Or maybe at some point try this 37mm factory Sandcast Mikuni with PJ

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matt.3150
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2/17/2026 2:42am

Insanely cool parts! Excited to see it finished and on a dyno!

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2/17/2026 4:11am

Insanely cool parts! Excited to see it finished and on a dyno!

With you on that one CD!    Throwing in two Fonseca 05 cr 250´. 

s780 89093160 1270541799fonzylgDSC 9562.jpg?VersionId=oVCtbl
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2/18/2026 7:40pm

Amazing stuff. Always a good day when this thread pops back up to the top! 

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matt.3150
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Programmable Honda HRC CDI


IMG 0575 7

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matt.3150
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matt.3150
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matt.3150
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Tokarski710
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4/28/2026 3:52am

Bike looks great! One of my favorite Honda eras, please make a bike check on this beauty so I can do a bike of the day on her. Cheers 

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matt.3150
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Bike looks great! One of my favorite Honda eras, please make a bike check on this beauty so I can do a bike of the day...

Bike looks great! One of my favorite Honda eras, please make a bike check on this beauty so I can do a bike of the day on her. Cheers 

Will do, I still got a few small things I’m working out before the first phase is completed. Once’s she ready I’ll do that. But I’m going to be doing a second phase of some updated things as a bonus later.  Thanks

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sandman768
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4/28/2026 8:32am

….would love to hear that bike…..just saying…..💪

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matt.3150
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5/13/2026 11:25am
sandman768 wrote:

….would love to hear that bike…..just saying…..💪

I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12 much easier to deal with MRX02 more power but a bitch to jet and will change thought the day. Maybe 50/50? Anyone with some experience with these 2 fuels and or mixing them

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Carson610
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5/13/2026 12:33pm
matt.3150 wrote:
I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12...

I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12 much easier to deal with MRX02 more power but a bitch to jet and will change thought the day. Maybe 50/50? Anyone with some experience with these 2 fuels and or mixing them

MRXO2 is great if you’re racing, definitely makes great power. Probably the best HP gain per dollar. I’ve only ran it in 125 and 250 two strokes. I don’t think it’s worth the cost and dealing with the smell for just riding.

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TxT0RKiT
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6/13/2026 10:59pm

What Matt said, its was $43 a gallon last time I bought a can.  MRX02 premixed is a little lean straight out of the can, it runs strong and smells the most like a factory race bike in my opinion.  I eventually added some 927 oil to it.  I going to mix MRX02 with T2 for my next test.  This could be the perfect combo.  

Here is straight MRX02 notice not one puff of smoke.  

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6/14/2026 12:06am
matt.3150 wrote:
I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12...

I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12 much easier to deal with MRX02 more power but a bitch to jet and will change thought the day. Maybe 50/50? Anyone with some experience with these 2 fuels and or mixing them

I think it was Roczens straight rhythm YZ250 or RV’s YZ125 that explains in a Youtube video that Mitch built it for a mix of MRX02 and C12 to help stabilise the jetting. I think that’s probably the best combo if you still dont mind some jetting faff but want the most power. Otherwise just neat C12 which is what I run

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matt.3150
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6/14/2026 7:44am
matt.3150 wrote:
I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12...

I’ll make a video when it’s up and running, still working on a few things.  Also deciding if I want to run C12 or MRX02. C12 much easier to deal with MRX02 more power but a bitch to jet and will change thought the day. Maybe 50/50? Anyone with some experience with these 2 fuels and or mixing them

I think it was Roczens straight rhythm YZ250 or RV’s YZ125 that explains in a Youtube video that Mitch built it for a mix of MRX02...

I think it was Roczens straight rhythm YZ250 or RV’s YZ125 that explains in a Youtube video that Mitch built it for a mix of MRX02 and C12 to help stabilise the jetting. I think that’s probably the best combo if you still dont mind some jetting faff but want the most power. Otherwise just neat C12 which is what I run

Yea that’s what I’m thinking 50/50

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