This one's gonna be a slow burner, I've been acquiring parts for it over last few years and I've still got a long way to go with fabrication and custom parts and getting the right things. I just got the cases back from a machinist buddy and am excited for the hurdles to come


Re: slo-burn

At least they seem fairly clean . ;)

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Trenched them to run a minarelli crank? Nice!

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todd amundson /

How does one seal that razor edge? My hobbit cases with Derbi crank leak all the way around.

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Case bond needs more purchase then that, unless you upgrade your fasteners... if you can.

The other solution is a thin copper gasket, and case bond... if things are well balanced. This is all tear down and inspect after every race shit. Somehow, race build and tune isn't suited to street riding type low to no wrenching after blasting...

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Brandon Weiss (Detective brandon to you) /

Looking closely, it appears that the sealing surface around the crank has had jb weld added and milled flat for more surface area.

Should be fine with a high quality anaerobic sealant. Although, with all that work, it would have made more sense to have it tig welded

Re: slo-burn

Jb weld should work fine in this application. I would not recommend filling in that whole area with weld. I bet it would warp the cases, even if you went suuuuuper slow. Shannon had a set of cases that were trenched to run a start 3 crank and they were built up around the crank journal, it never ran right. (edited)

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Some progress. I dislike subframe type things so hard mounted motor with new swingarm mount. Gonna get motor more together before finishing up frame. Right now its looking like pipe is into the rear pulley, I wanna get cylinder spacing set and go from there


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Totally normal JBOT /

That is very nice

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Chubby neon pegs and a fat disk brake for those who like to endo

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banshee reed adapter coming up next. I think pretty much largest block I can fit between engine mounts


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Wow I dunno how I missed it but this is pretty wild, can't wait to see how it turns out.

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Got reed adapter mostly done, it's tacked and just needa tig it up, then getting the warp & leaks out. Fits into the frame pretty nice, might even be able to fit that center cover. Pardon my shit welds


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The JB weld is going to run out if you tig the cases now

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Tig for the reed block, cases should be good

Almost done with case matching, just got some final shaping and smoothing. Didn't needa go super deep, the way the transfer cutaways are on cylinder let it open up. Figure the custom reed block adds some case volume.

Might be a bit until next update, waiting on some parts


I fell in love with this exhaust port


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Totally normal JBOT /

That is fantastic

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Sooo kinda getting into some crackpot ideas here. Strongly considering running my variator backwards, like the cheek moves towards the case with variation.


With the variator in proper position belt alignment is wayyy off, like the ramp plate is too thick? I cut the crank a bit to get it sitting in as close as possible and still not enough.


With the flipped variator the centerline of rear pulley and front are pretty much there. Probs gonna try this before dropping $ on another variator


Idk what those spanish dudes are doing for variators, like I got mine as far in as it'll go. Variator is a polini evo for minarelli horizontal. Idk if other ones have a shallower ramp plate or what

On the hunt for the correct belt now. Derbi piston port is too short, 628mm x 17.5 wide. I got a stock dio belt at 654mm x 18 wide and that was too long

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Better pic of how close the ramp plate sits:


Also got ignition adapter done


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Mostly plumbed up


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Motors together, fingers crossed for the leakdown test tomorrow. still waiting on some transmission parts tho :/


48.7mm stroke crank crammed in there with a 50.5mm bore, roughly 97.5cc


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What’s the crank for? Horizontal?

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Yep! That's what it's advertised for anyway, from what I've read jog90 cranks aren't too far off from this? It's an mvt sc crank. It was pretty close for side to side width and outer diameter still fits between case bolts. Had to clearance conrod a bit. I bought it under the impression it was 95mm conrod and it is actually 90 so my port timing is a bit jacked. Gonna see how it runs before checking out swapping rods


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Well my intake leaked, so got one from crank pipes ryan on the way. Getting other shit done in the meantime

3/4" delrin spacer for spacing out the kickstart cover to clear the longer scooter crank. Gonna cut away some more of cover when I get variator finalized. Does anyone know what other kickstart lever splines will fit on revo covers?


Got pipe mount & pegs figured out. I wanna find some pegs that fit these offsets that are a bit more of a platform. Steel would be dope, hack n weld em up with the end of some pedal arms to get pedals.

I got a bit creative with some spacers and was able to lower the pipe just enough that it clears the pulley and didn't have to chop n weld it. Basically 15mm longer at the header, but that bit of length should hopefully play nicely with the increased port timing from shorter conrod.


Finished up frame welding. Gonna grind down a bit then either poorly spray paint it or sandblast & powder


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I don’t know of any other spline that works but I’m sure it’s out there.

You could cut a slot and put a pedal cotter pin in? Just an idea if you can’t find a lever.

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Getting fancy with the electrical. Koso db02 multi gauge, h4 led conversion. Got an antigravity ag401 small case battery fed by rectifier regulator. Working on getting everything tucked away, but battery fits under tank real nice. We'll see how the cast is on the h4 led. It's 36w so hopefully pretty bright with a similar power draw to incandescent bulb.

Got it all sealed up, ended up using a dead Gila piston to plug my intake, lol.


Talking with some dudes from spain, hopefully getting some belts shipped over. The one I've seen fit on other overrange setups is a gates 9802-21506 (edited)

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First start today! Still waiting on some parts, needa get the right temperature sensor before I can get coolant in. No luck yet on the right belt for the overrange, using dayco 8004 from piston port in the meantime. Gonna mess around with some pedals and get them to mount into the peg dropouts. Similar thought with the kickstart lever, might end up switching to a forward kicker depending on foot space.


It's been a long time coming, feels good. Got cylinder probs 3 years ago with the intention of hacking up scooter cases into single variated. That never really went anywhere. After blowing up my Gila piston port on this frame last year, this idea started to materialize.

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Got my pedals and kickstart lever figured out! Made the threaded ends of pedals match the pegs that these rearsets came with. Kickstart lever is an ebay gy6 one that got shortened and forced on.


Still on the quest for the perfect belt! Still haven't tried that gates 21506, I bet that's some goldilocks shit. This is with piston port flatreed belt, dayco 8004. Fits but too short to take advantage of overrange. Roughly 628mm outer circumference.


This is with d&d 1228v255. Just a bit too loose. About 660mm outside circumference. Not sure how low it goes in rear pulley at max variation yet, haven't gotten there. Between this belt and dayco 8004, I like 1228v255 more, but still holding out for the gates.


My biggest problem before I get too deep into variating & belts & shit is figuring out jetting. I got a 228 in there and it still gets kinda lean boggy. 38mm oko. This setup is $ enough that I wanna hear fourstroking forsure before getting too hard on it. I've not had the best luck finding PWK jets north of 230, like the one range that size I found on ebay is taking it's time to get here. (edited)

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Totally normal JBOT /

Can’t say much more than it’s a super sweet build

Re: slo-burn

Just swap to a skinner needle.

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