Dax KTM 50cc clone build

I have been running Mobil one atf fluid with my tomar clutch . That's what the tech guy said to use if I didnt have the cool blue fluid . You can also put a couple of ounces of two 2 cool in it . They claim a 20 to 75 degree drop in temperature.
 
I have been running Maxima's heaviest weight clutch oil from day three without a single issue. All I had to do was adjust the clutch and then simply ride it hard like I have always have ever done....

Best clutch this bike has ever seen. To me this Tomar clutch is flawless. I love this clutch!!dnut
 
All I needed to do to get a workable clutch with my Martin and Slater clone was to put a hardened machine washer under each puck post, and I drilled oiling holes in the pucks for the beleville spring washers and stacked them all ( ) ( ) to each other, works great so far, you need the right gearing for the stock clutch to work, like duplicating the chain tension on a KTM50. If you try and lug the motor and spin the clutch away its bad, I had that problem and gearing made the stock clutch work like butter. I use Redline brand D4 ATF in my case, about 250cc.
 
Yeah those tiny mods made one heck of a night and day difference in that stock three shoe with the shimming out to the bell etc.. My best days with my old three shoe set up are very similar to this Tomar clutch some times but very rare considering. Tomar wins hands down in my experience now days.

It just needs no where near the same maintenance than before for me now. I still had to clean trash out of those old washer stacks and felt lucky if'n I adjusted the three shoe spot on.

My Tomar clutch in my experience so far simply works perfect '''all the time''' no matter what!
 
I certainly hope I don't experience such a rapid degradation of performance. So far I've ridden one ktm clutch service interval, and the oil is fine and the operation of the clutch is improving actually. These clutchs are quite inexpensive off Ebay, if I have trouble with the beleville washers gumming up with clutch dust, then I'll try out the coil spring kit that I purchased for it, which I doubt goes to full coil bind so the junk in the pucks wouldn't matter as much.
 
I'll admit I did have one unpleasant moment yesterday climbing the biggest hill I've ever encountered in this county with my clone engine yesterday. Going about 25, I didn't get a good enough run up the hill because I used the bike lane, and had to wot it on the edge of slip and it got me to the top of the hill but I know it must've frothed the fluid because my bike was oily, and the motor got very warm. Next time, I'll have to remember to get a good run and "race" up the hill at 35 or so to keep the clutch engaged, I lightened mine so its at a taller stall speed. One must remember that with a centrifugal clutch set up for moped speeds you need to get a good run up steep hills.
 
Hills don't effect me. My clutch fluid does not froth up. The oil I am using has anti foaming agents in it. I and the bike equal about 360 pounds + more with differing amounts of cargo, groceries etc .

Once a month or so I bring home a 40 pound sack of dog food home draped across the bars. Hills are every where here we got's a mountain. ''The Sandia's''
 
Sure a hill effects me I will get a slower start If I am in the middle of it. The bike always go's to mock speed tho regardless. Full speed red line..
 
I installed the Tomar. The big metal spacer to widen the case is about 9.5mm, plus another .1mm for the extra gasket. That's a lot on a motor that is extra wide to begin with. I was able to grind down the inside edge of the pedal crank and file the case slightly so the pedals can turn. It's shakedown time; making sure nothing vibrates loose, especially the front springer shock forks. It would truly suck if those came apart. I'm pleased though that the motor is perfectly balanced and smooth as can be.

I don't plan to run at wide open throttle all the time, which seems to be required with the high rpm engagement. That would burn tons of gas and probably burn the clutch too. I would like to be able to just putz around the neighborhood at normal bike speeds so I'll probably try for a lower rpm engagement. If a china girl can go 20 then I don't see why the KTM clone has to rev like crazy. It's a pain to drain the ATF so I hope I don't have to adjust it too many times.
 
Unfortunately these motors like to rev, that is where they make there power. To run it like you want to you might try a shift kit like wild bill did.
 
why would someone buy a motor that was built to scream and then lug it around? to each their own but sounds like they should have got a s-6E. perfect for cruzing around for years. smooth and quiet, sips gas and the clutch engages at low rpms. they put them in entry bikes and quads. same bottom end as the racers but small ports and a two shoe clutch. i'm just putting this out for people that want a nice well built motor that is not a M/X motor and they can use as daily transportation with out feeling your racing to work. dennis
 
headtrama said:
Unfortunately these motors like to rev, that is where they make there power. To run it like you want to you might try a shift kit like wild bill did.
Click to expand...

The cruising low speed and not wanting to rev the heck out of it and slip the clutch so hard is why I tried the shift kit. The bonus was it actually has held up to over 3 gallons of run time and a day of fairly hard use on an actual race track in an actual race. And besides its just plain ole fun shifting and it sounds like a CR 125 going thru the gears. I never intended to race it when I first built it, but the low gears really help getting off the turns as long as I remember to downshift all the way to 1st gear....lol
 
Turned out it didn't kick out much fluid at all so it must not have frothed, when I drained it I got maybe 10-15cc less than the fill out, if it was foaming it would've kicked half of it.

The "hill" was a 1000' climb in less than a quarter mile of road. If you do the exact setup that worked for me on my particular bike, it'll accel like a class C 4 cyl sports car and cruise at 25-30 at a quiet engine speed. Go with cars (people always want to go 45+) it gets noisy.

turbo NOS titanium LED underglow KUmhos
 
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happy to say it runs pretty well. I shortened the throttle cable by cutting off the end at the throttle, and cutting the sheathing part down with a Dremel tool. For a new end fitting I got a small wheel spacer at the local hobby shop, drilled a hole perpendicular to the tightening screw, ran the cable through that and soldered it in place. That worked perfectly and the wheel spacer was less than $2. Lowering the stall speed a little seems to have helped with drivability. The exhaust is getting there and looks pretty good. Now I need to make the gas tank look nicer. Maybe they will let me post pictures some day.
 
Glad to hear its running, hope to see pics sometime. And remember, that thing should be crazy fast, be real careful!
 
I recently bought a KTMC as well and mounted it in a Felt. What kind of revs are you seeing out of yours, I bought a little digital tach it wont get past 9k even down hill and seams a bit weak compared to my pk80 even at WOT, fuel is 25 to 1 it does not seam to be over geared. Did you have to replace the main jet to something smaller? Any suggestions would be awesome thanks.
 
Mix it at 40:1 with a good synthetic two stroke oil. It should run closer to 11000 rpm. You may have to reset it still.
 
I have tried running it at 40:1 as well it wont even hit that when I pick up the back tire and give it gas. The 25:1 was supposed to lean it and nothing changed. Are you running the stock carb? What will resetting it do?
 
You should be running 40:1 25:1 is rich way to rich .I am running a dellorto carb now ,There is no magic jet number that works in every motor . Jetting will change with temperature humidity and elevation . What main jet number are you running now and have you checked to make sure the jet has not fallen out .
 
It's been a long while since I fooled with this bike, but I had some time lately... The clone motor's kick starter was slipping more often than engaging. After looking at an exploded diagram for the KTM mini adventure I realized that the spacer washer was installed incorrectly. It was assembled with the washer on the outside of the case and it should be inside. Looks like this assembly error is common. It works a little better now. Getting that spring back in place is tricky.

The Tomar holeshot clutch is still slipping more than I would like. I imagine this clutch should really hit hard, but it doesn't grab nearly enough. I took the one shim out to reduce the air gap. I also lightly scuffed up the steel surfaces with 400 grit sandpaper, figuring they might be a little too slick. I might try some weaker springs - not sure what else to try with it. Maybe the gearing is a little too tall.
 
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