Just picked up my slightly used '24 YZed 125 the other day! The bike came with a FMF Factory Fatty pipe and a Powercore 2 silencer, a JD jetting kit installed, Dunlop MX34s with 1 ride (front still had the tits), Emig lock-ons, and everything else was stock. The first thing I wanted to work on was the suspension! If your bike doesn't handle good, you're losing time on the track and also putting yourself at risk for possible injuries...!! I want my bike to handle the very best it can and not do any funny/weird stuff on the track.... Smooth and predictable is where we want to go!!
Pulled the forks and shock off, tore those babies down, and let John Mitchell at https://Jm-Racing.com work his magic with his great valve specs!! We bumped up the fork springs to .45 and left the stock rear spring on for now. As you see above, I pulled all the linkage down and cleaned and greased everything with some high quality grease, and did the same for the front steering head bearings. You should absolutely do the same to your bike!! My build on my 2017 SX250 has a great write up of how to properly grease these components. Check it out if you're unsure.
Mounted some Hoosier MX25s that I pulled off my LL24 ride ('05 YZ125). Ya, the used MX25s hook up and corner better than a new set of MX34s! I've ridden them back to back and the Hoosiers out perform the Dunlops, Hands Down! They're made right here in the USA by Americans! I ride the same tires that the Hoosier pros ride, and the support I received at LL22, LL23, LL24 was incredible! Check out the tires at https://www.hoosiertire.com/tires/motocross/ Check out my LL24 write up on Instagram. @KeatingTraining121
Added a tooth to the rear (50T) to help the stock motor out of the corners and get on top of the power band a little easier.
She is back together and ready for some testing at the track!
Performance Reviews, Updates, and more to come! Stay tuned....
I agree the Hoosiers feel alot better than the dunlops. I'm slow and I can feel a very big difference. Just sucks they wear out so fast.
Yes, they do look worn fairly quickly. Eric ( one of the Hoosier guys from the N.E.) told me that they'll still hook up and work great even when they look pretty worn. I gave it a try and he was right! I ran a pretty worn looking set at my last race and it hooked up great and work perfectly! I felt no problems with the back not hooking up great or the front not grabbing in the corners...!!
On your next set, just keep running them past them looking worn out and see what you think.... You'll probably be surprised...!!
First ride and things are a little lean.... That pipe was silver in the shop....
After the first moto, pipe was getting a little blue, and after the 2nd, that baby is PURPLE!!
The JD jetting is definitely too lean! So again, JM Racing came through! Stephan ( JM's personal Romanian factory mechanic) had the fix! He changed every single jet in the carb, including the power jet and this baby now sings like Greta Van Fleet on Highway Tune!!
So sweet,
So fine,
So nice!
Haha!!
Stephan won't say what his specs are, but they work...!!!! If you're running a '22 or newer YZ125, you better send your carb to JM! Made a HUGE difference!
Track was 3 Palms... Way too smooth for any suspension testing. Will have to update later on how the suspension is working.
Stay tuned!
I haven't ever seen those Shock Sox. Are they solid plastic or a nylon fabric? How effective are they?
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The Shock Sox are awesome! I've been running them for years and love them!
They are a nylon blend with velcro fasteners. 10 second install and you can throw them in the wash with your riding gear!
First fork seal leak that I've had in years!! I didn't have any Shock Sox in the van at Thunder Valley for the LL24 Regional and this is what happened. I switched bikes at the last minute and thought I had extras in the van.... I didn't...! Never again!
Loretta Lynn National 2023 was a huge mud race!! My fork seals never even weeped. Guys were blowing fork seal everywhere!!
Check 'em out!
www.shocksox.com
Jetting on that bike is a biggy. A lot of riders it takes them months to get it right . He must be pretty good. I hv numerous needles 1/2 step leaner, richer, way leaner main, pilot . I never saw such a purple pipe. I hate plated pipes but that’s all I hv and 3 stockers. 1 with a dent in the cone it hits harder . I forgot I hv a 03 hgs Budd raw pipe , not done fitting it to the 04 cr125. I really wanted to do AX 125 all star class and 40+ . A Tx. Rider did most rounds of the GT series . I think the 125 would do great on the tight tracks. To make a pro main would b tough . I think they dropped the b main . The other series has it tho.
Ya, jetting is tough to get just right! This new YZ125 has a power jet also.... but JM has the perfect settings!!
AX main on a 125 would be tough! And Very Fun!
Got in a few motos at the Moto Masters series here in Texas at TAPT house track. Day went good. I won the 50+A which was run with the 55+ & 45+A classes and beat everybody, so, technically I won all 3 classes....! Haha I also got a 2nd in the 40+A with a 2-3.
So this well used tire got me out of the gate 1st in 2 of my motos and this Hoosier baby hooked up so well I blundered and had to chop the throttle in the othere 2 motos... Like I was saying earlier, these HoosierTires work great even when they look all used up.
JM suspension was fine, track didn't get super rough with a light turnout. Still getting used to the bike and its working great!
More to follow, soon!
Suspensio Shock Work!
a busy month, guys! However, I've got some updates! Probably the biggest change we've made this past month was the addition of the Triple Adjuster to the JM Racing specs shock...
So, there are a few bikes that come with this Extra cool KYB adjuster, but the YZ125 is not among them. John Mitchell helped me out with the maching of a spacer so the Triple Adjuster would fit in the shock body. The YZs have a different body and shaft then the YZFs. So John told me, "no problem" and headed over to the laith and started machining me out a spacer!
Turned out quite nicely!!
Fit like a glove. We got the shock back together, set the clickers at 10, 10, 10, and 9 on the rebound for a base setting and mounted it on the bike. Set the sag at 101 and headed to the test track....
Shock felt great, although the track wasn't very rough (always a disappointment). So I was going to the slower lines looking for bigger bumps and that was a little better for testing. I was able to over jump and still keep the plushness on the smaller braking bumps, but didn't have any really harsh sections to put this new shock set-up through the ringer.... So....Road trip! The fam was all going up to Colorado for some vacation time and see my parents. We stopped off at the Canadian river just North of Amarillo where I grew up riding and I knew I could find some gnarly testing areas that would be great! The "river" as we have always referred to it as, was perfect! There were stretches of knee deep whoops for days and a few choppy square edges that would rattle your teeth.
I haven't been able to really find any literature on exactly what the Triple adjuster is capable of so I was flying blind a little bit except for some hear say. For me, the Ten adjuster worked really good on choppy stuff and the Rebound adj on the bottom of the shock I used to slow down the big rolling whoops and larger square edged curbs. It was more of a reverse for the compression adjusters, I turned out the Low Speed to speed up the shock for the braking bumps and slowed down the High Speed to hold the bike up and be able to stay on top of the deeper rolling whoops and large jump landings. This was just 1 day of testing with 47 stops to grab my trusty flat tip Craftsman and so I only had time to try this direction and it worked really well for me. I do plan on more testing and trying different settings, so, stay tuned for more. I may find a way better combo, and I'll let you know.
Right now I'm at
LSC 13
HSC 8
TEN 16
Reb 7
Sag 101mm sitting in the pocket
These are obviously paired with JM Racing valving specs and would be different if I was running stock valving....
Impressive dude...!
Some Cylinder Grinding!
Many folks are familiar with John Mitchell's exceptional grinding skills when it comes to engines mods!! He did my 2003 YZ125 flat top motor that I podiumed the 1st moto in the 50+ on at LL17 and Clayton Miller 2005 YZ125 that I've ridden for the last 2 years at LL23/ 24 with several top 10 motos and overalls!! My point being JM Racing puts out some Bad Ass engines! Obviously, I wanted him to do some magical grinding on this '24 also! Unfortunately, we were pressed for time with me headed to Glen Helen for the World Vets last week, but i needed some more ponies for those huge hills against a Sea of highly modified 150s and 125s in the Pasha 30+ and 50+ Pro 125 races....! So, John whipped out his grinding tools and hooked me up! Got her broke in and headed to So Cal. She ran great!! Pulled strong off the bottom, and even stronger in the middle with plenty of top! Went into the 1st turn in the top 5-6 and let off too early, damn it! Came out of Talladega about 10th, lost a couple spots in the first few corners, passed a couple guys on the down hills with my great suspension, ran around 12th for the moto, but faded at the end. Bike ran great, and we can get some more out of it!
I'll keep you posted.
Sounds Great r you thinking about getting a ignition? John,s engines are amazing 5-6 on that Long start is impressive against 150,s. I finally got my JM Racing 04 cr125 together. The cylinder is on my practice bike bottom end . I just had to see how it ran. At 1st I thought nice snap & more everywhere. Finished the heat cycle . Then 2nd ride Holy shit rolling stab the clutch in 3rd the wheel snaps at the sky . A quick stab of the clutch & it hits 19.9 ft lbs Rt now then pulls hyper threw a Much stronger & Longer mid into ovr rev. real quick Exactly what I wanted. fmf with a shorty, rad valve, iKat , c12 , different carb taper bore. Power flow air cage& filter. I think my ignition caught up between heat cycles. My c12 is 15 months old from bulk, it was in a steel vp can though. I think fresh fuel it would b better. A lot of Wi. 85,125 hv JM engines. Great engine for our sand& loam hilly tracks. GH Hillls are much bigger how did your 125 pull them compared to mod 150,s ? Not sure why but my wt is not 172 anymore it’s 162 ish. Working a lot on the rd now.
Coming up on 40 hrs, time for a some parts.... Went with a Pro-X rod, OEM Koyo crank bearings, OEM piston kit, and some more grinding fron the man, John MItchell! While I had it split, I wanted to get the cases matched up to the cylinder and get them touched up by JM and see what kind of power we could get out of this baby!
Looking nice and clean!
Also had https://Trickeng.com coat all of my transmission gears along with some other tranny pieces to make it ultra slick and turn as free as possible.
Obviously, the stock tranny looked great having only a few hours of use... I was surprised to see some of the gears and shifting drum had been heat treated, they did a nice job.
Let's see what Trick Eng can make happen...
Everything came back looking amazing! I can't wait to see how smooth this baby shifts....
Stephan at JM did an amazing job on pressing my new Pro-X rod together and truing it up with ZERO movement on the truing stand! I've got a video on my Instagram, ck it out. https://www.instagram.com/keatingtraining121
Went with a complete tear down of the bike for her 40 hour framing also.
Completely framed it, greased the linkage/steering, serviced the suspenders, greased the all connectors, and got it back to new as possible. She should fly like a Peregrine falcon. Gonna get her back together and throw her on the dyno for some different pipe testing.
More to come!
I can’t get the link to work bad phone service. Is trick engineering micro polishing? Ever see the UK tuner vids he tried 2 ignitions , a VHM crank, he runs hgs pipe popular in 125 emx. Does John program ignitions? It’s tough to find 1 for my 04. Budd said they could get 1 out of Europe but it would take time. I took grinder a tiny bit a paper thickness off the hole where the pv shaft goes in. And polished the rollers on the shaft. Much freeer & smooth pv operation now. Matched the exhaust flange that bolts onto the cylinder. It had a 1 mm ovr hang. Little stuff to get everything out of it. I split my cases never got my trans gears shipped to New England gear . There 260 bucks I think . I want the gears to turn easier etc but for durability also. All that extra Torque you running a complete Hinson clutch ?
You can just google Trick Engineering. He does welding and fabrication, along with coatings, and some CNC work....
I'm gonna check out the UK tuner, for sure. JM runs some VHM cranks and John does some programming on the GET ignitions. I'm not sure about getting a '04 CR ignition, that sounds pretty tough!
The polishing on the PV sounds like a good idea, and I've seen some bolt on exhaust valves that don't match up very well too.
If you haven't sent your gears off yet, you definitely should check out Trick Eng. His coatings do exactly what you're looking for and they're here in TX.
I just started my 2nd set of OEM plates at the World Vets. I've ran a Hinson on my 07 CR250 and wasn't very impressed.... I really like the Rekluse plates and their set up with extra plates and the thin steel barriers that protect the outer basket! I'll probably go with that set-up on my next clutch.
There’s a ton of bolt on tuning combos for your bike. And ported mod combos hard core racing is the UK guy. White yz vs a am natal champ & winner of the last 125 Uk natl. on his mod 125 Ktm .They run crap fuel so there down 1 hp to a PC on mrx2 gets 38. ? I think my bike is pretty equal to a PC RV spec with the RV pc pipe . My bike runs alot cleaner tho. Most yz builders r going for more everywhere. None of them went for upper mid to top .
Are you saying that the UK guy built a KTM that was 1 hp less than a Pro Circuit YZ? One of the bikes is putting out 38 hp? I didn't quite understand what you were saying....
Sorry this cab has super crappy lighting I literally can’t see it messing me up bad mentally not good to b in a dark hole. The countless yz vids the Uk mod bikes seem to be 1hp down at peak to The PC RV spec. But that would be the mrx2 or whatever the 50 per gal fuel is called. The main hop up uk guy Rolland of hard core racing goes for more power everywhere.
Pit Row
How are those Hoosiers holding up at 40 hours? In other forms of racing they call Hoosiers "Purple Crack" due to their killer grip but short life and it sounds like they are living up to the nickname in MX too. Factory riders change tires every race so they shouldn't care about life but they are also sponsored by other tire companies and get forbidden "spec tires" that act like Hoosiers. Maybe the "spec tire" movement is to keep them off of Purple Crack.
I'm still loving them! I put on different set for the World Vet race at Glen Helen at 33.4 hrs. They were actually slightly used; they were the tires that I ran at Loretta's this year on my buddy's bike. So, they had 2 practices and 6 motos on them.... I"m telling ya, they look worn, but they are hooking up great and every ride I have on them they are inspiring more and more confidence for me in them. It's surprising, even still. They have not let me down, not once!
You can see one of my starts on my Instagram. I came off the gate as strong as any other 30+ ex-pro on the line.... https://Instagram.com/keatingtraining121
Will we see Keating/Professional125 team up for the big $ vet races in 25?
Hahaha!
On well used Hoosiers...!!
Hoping to get into a nice used 22+ YZ125 to upgrade from my 08 YZ125 with almost 700 hours on it. Love the case matching. I should have done that when I did the last crank in my 08.
You can have it done on your new one....!
Sounds like fun . I ,d like to team up with someone, maybe a fast 50+ riders rocket fast 125 rider . For riding & training his dad is busy running a Mx shop. Being that it will be July b4 I ride , if injections on the bod work . I,m racing 2-3 weeks 125,40b, 50+ has 10 riders that can win much faster than 40b . But money is soo bad out here .Bike cases r split , van needs frontend rebuilt, etc. After 2-3 weeks 30A for sure just to get my speed up a couple races learn the pace . Chad Johnson wins it & both motos at a pro am in 450a . The rest can race big vet stuff like red bud & Aztalan & do good. Then maybe 250a chase points , 40a try to make a little cash , 125 class for fun to win a moto would b Huge. No chance of winning these classes but u get faster. I can drop 40a & do 50+ at some tracks to get a better chance at winning. Even in the Up of Mi. There’s a guy that goes 2-2 at red Bud big gate 50a. So the competition is everywhere. Millville has a double header 1 day is the Viking clash usually a bigger gate in 50a & cost more so more money on the gate.
What the f my long post was deleted when I uploaded pics . Probably for the best but I really don’t hv the time to waste. This pc rv bike runs better than RV,s Or cleaner . See this #18 tiny kid that’s basically the 125 class in Wi. Little rippers
That 125 race was very cool, even though I had no idea who was leading or what was happening in the race.... It was still fun to watch and LISTEN !
Had some down time this winter and just rested my body mainly, and rode my '03 a few times up at my buddy, Michael Gage's neck of the woods in upper East Texas. He's got some incredible places to ride within 30-45 min of his house! Been doing a ;little training and am just now ramping up my program for the LL25 regional qualifier.
It was so muddy at one of our practices on his rut track in December, we had to watch our bikes in-between our motos....!!
Been doing more cool stuff with my YZ125 race bike down at JM Racing....
Got the degree wheel fitted up and we are working on port timing and squish numbers...!! We aren't publicizing numbers, but I wanted to let everyone know what kind of program JM is running and the extents they go to for fast reliable engines!! I'm looking for a little more bottom end to help this old man get out of the corners a little stronger and help me run with those big ole 4 fiddys...
Another tip is the Moose clutch lever/perch on my bike. It has 2 cable attachment positions. The position closer to the bars gives your bike an even easier pull. Yes, it's a 125, but it can't get easy enough for me when it comes to clutch pull ease!! I can fan the clutch on this baby with one broken finger, speaking from personal experience.... I run this set up on all my bikes!!
Also, in the middle of testing different gearing. More updates coming soon!
I just made it the trk yard drinking coffee to get trk unloaded & drive my van home. Horrible winter & money is terrible. Pulling the plug in a few weeks get a few body parts injected. And get ready to race probably sell a 04 of the 3 to fund a part of it. #1 is chase points in the 125 class possibly race Deschambault in Quebec week long LL type of race then premix again on Sunday. That weekend is Xmas Big race double header. So I don’t know if it’s close in points I,m skipping Quebec. My JM Racing 04 cr125 runs amazing it’s crazy how good it is. Last sat I showery the pilot at the LL exit 83+ muggy with high dew point & a lot of severe weather in Tn. Your mud riding will probably come in handy . Snow in the forecast for Monday & it’s still cold up north.
Stay warm!
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