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Only $10 for all 2024 SX, MX, and SMX series (regularly $30).
Of course, it would then require someone younger and MUCH more talented than I am/was to ride it!
Did you give any thought to running a Lectron or APT carb? Did you decide against one because of the programmable ignition that you're using? Thanks.
The Shop
We also added a SDI elite shock clevis with a rebound adjuster because the stock rebound adjuster on these shocks is basically useless. The linkage is stock but was prepped by Justin at Motowhips. They remove all of the casting flashing from the knuckle and link and polish it to a satin finish. It looks really clean and actually cleans up much easier because the surface is much smoother. We did the same process on the rear brake pedal and kickstarter. The titanium linkage hardware is from RaceTech Titanium.
Below is a before and after shot of the linkage.
Now you mentioned "2. As lightweight as possible". I like this but can't help but notice you've added a few items that may increase weight in a few areas. Do you have a target weight? Also, I just wanted to get in on that before everyone starts in with the eat less and shit more comments.
And that tranny is just pure damn sweetness. I have a vintage project that may be getting 6th gear tossed.
Keep the pics coming, love watching other people spend money on cool stuff that I like!
Varner then added the necessary mods for the 3 speed trans and did the final clean up and prep.
That ignition website is cool, but I didn't see anything for the rm125.
Also, if doing custom electronics, try cycleterminal.com since they have oem type waterproof fittings, you can make tps tools and other stuff.
Nice project
407.880.6163
rcr811@aol.com
I'm a fan of the RC engine too, getting great results from minimal mods on an 02.
I can't remember if they have the gear position sensor also? Hooking up a map using the TPS, gear position and revs and adjusting the RC opening to suit would be a bitch but awesome when achieved.
I think you'll be just fine with the 3 speed transmission. I had two '02 CR250's that I used of Offroad racing and never used 1st gear even in tight woods. 5th was just for long WFO runs.
Pretty much the same with my YZ.
I was into the 2002+ CR motor, also. Thought there was a lot of potential there with the electronic PV. If I had been able to find an ignition like that back then, that would've been tits.
Maybe I can build a Servo PV for my YZ?
Pit Row
Didn't they change the stock RC powervalve motor with some hi-po RC motor..a 380 mabuchi?
What kind of insane Horsepower numbers do the cart guys get?
Use Bikemaster non-HD tubes, they're very light at close to 1lb each. Some guys have even begun using mountain bike tubes (26" for fat tire bikes), which seem to be working okay and they as a pair weigh close to a pound lighter than the lightest motorcycle tubes.
Motion Pro Liteloc rim locks, Motion Pro rim strips, Pirelli MXMS tires (110/85-19 rear is super light, and lets you go down 1 tooth on the rear sprocket). Stock Honda wheels will be lighter than anything aftermarket, get the hubs lathed and polished or anodized. Talon rear sprocket, Sunline MXMR chain, OEM front sprocket, CRFstuff rotors, and you will have the lightest wheel set possible.
OEM Honda plastic is lighter than anything aftmarket too, with the exception of the Cycra stadium front number plate and vented front fender. If you insist on a graphics kit get it printed on 4mm vinyl.
It will be possible to get that bike under 200lbs but you will have to be very careful of parts selection and not adding anything extra on that isn't absolutely neccessary like disc/caliper guards, twinwall bars, etc. Air forks would make things a lot easier for you, KYB sells the PSF1 works forks which are what most of the factory racers seem to be currently using. Go over the bike with a fine tooth comb and remove anything that doesn't have to be on there. Many little things add up. Use aluminum hardware where possible, it's lighter than titanium.
The new NEXT unbreakable clutch perch assembly and front brake lever are the lightest on the market, too, if you plan to go non-OEM.
I assume that you already know a lot of this stuff but just sharing what I've found with my own lightweight CR250.
Sounds like a fun project, can't wait to see the finished product!
The Dixon bikes were rev monsters, and the camchains wouldnt do more than a day, because they had to rev them so hard to get them to work with the 3 gears. Also the high revs killed the cases, which is why they went billet.. Osborne used to crack them after 3 race weekends apparently.
Awesome work though , if i had the time i would send our gearboxes to REM finish over here , just because it looks so damn fine.. it makes a huge difference , i know we ran a set of non REMed gears on the rig just to test some stuff while we were waiting for others to come back, it was measurably better .
They are solid mount.
The problem with using an X-Trig pre-load adjuster on some A-kit shocks, is that the reservoir offset can be slightly different than a production shock. Or in the case of a KXF A-kit shock, the diameter of the reservoir is a bit larger.
Mlindsay@vitalmx.com
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