125cc Supermoto - 2 Stroke goodness

[binge]

Wont go into too much detail on here. There is a project thread on the 125cc sports bike forum, and some captions of it on the PitBikeClub too.
I'm not gonna to into depth across three forums.

But, this evening I've been doing this:

https://i902.photobucket.com/albums/ac227/pitbikeben/20140110_191701_HDR_zps691fb90d.jpg


And then I did this:

https://i902.photobucket.com/albums/ac227/pitbikeben/20140110_220142_HDR_zps7c5b390d.jpg


It's a Rotax 123 engine, and a Malagutti Drakon frame. Mounts are so close it's un-real. 2 of them line up with no mods at all. Other two can be made to fit very easily.

Top shock mount needs re-locating, and I need to fathom around with the sprockets to get the chain to line up.

Other than that, it's going together quite well.

Should be nippy.

[binge]

Oh, and it's a Road-Legal frame. So I'm well within my right to go hooning!

[stevo as b4]

Just epic!

That proper stiff beam frame with a decent box section cradle has got to be stronger and better than a pit bike frame for 30bhp antics IMO!

It's great to see a different build being done and something new! is the front and back ends just high spec pit bike parts, or from other bikes?

Me is thinking that a copy of this with my KMX200 motor would be better than buying a KSR80 if I ever found one?

[binge]

Yup. Forks are Marzocchi replicas (Fully adjustable though).
Rear swinger is imported, but it's a solid billet unit. It's the same as the one I had on my last 2 stroke pitty.



Didnt get a massive amount done today as I had to put two new sills on a KA, and fit a new exhaust system on a Golf.
BUT, I did get a few bits done, which have allowed the carb to fit now, and given plenty of room for an Air-box.

Before I started:

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_113615_HDR_zpsc0585a85.jpg



The with the shock re-located, the carb fitted straight on.
Mocked up the exhaust. Had to chop the bracket off, and cut the stinger pipe down. but it goes on.
The pipe does swing under the bike more, but I lent my welder out ages ago, and need to get it back, so have not had chance to make any brackets up for it.

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_165415_HDR_zps37dcd3e2.jpg


Looooooads of room!

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_165422_HDR_zpsaf1afa87.jpg


Nothing is done up tight, so it all looks a little twisted.

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_165433_HDR_zps18a7d100.jpg


https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-frc3/1507029_10152119193620606_1441996334_n.jpg




Ben

[binge]

Oh, and I started cleaning up the engine:

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_183326_HDR_zps74e0bbdb.jpg

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_183337_HDR_zpsc6a6ea7e.jpg

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_183345_HDR_zps2b94f438.jpg

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_183354_HDR_zps902213b9.jpg

[Kickstart]

Hi

Important mounts are the big ones at the back (swinging arm spindle goes through it on the RS) and the front one under the exhaust. Personally I wouldn't worry too much about the ones underneath, or the ones on the barrel (the original AF1 with the 127 engine only had the 2 main mounts, and the front was rubber mounted as it had no balance shaft).

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[binge]

Cheers Keith.

I will be keeping the swing arm pivot one through the back of the engine.
The big mount under that one, lines up with the frame rails, So I will be drilling the frame right at the bottom, and passing another long bolt right through that one too.

Then will make something up for the front.

Should be getting my ARC welder back in the morning so I can start fabbing some bits up.

[binge]

Messed around with the top shock mount. Needs welding when I finally get my ARC back.

Also fitted subframe, and moved exhaust to other side.


https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-prn1/1560744_10152121495555606_591072601_n.jpg

[1cyl]

I saw this pic and instantly thought "vagina"

https://i902.photobucket.com/albums/ac227/pitbikeben/20140111_183354_HDR_zps902213b9.jpg

Good effort OP. Keep up the sterling work .
____________________
Chase my Witch up, Catch my Snitch up.
The SMC | The Pit | Stable

[binge]

I don't even want to know what sort of monsters you've been pushing around if you've seen vags which resemble the inlet on a Rotax 123 engine.

[mysterious_rider]

Looks savage ben, I gave up on my nsr one when I realised the wiring was botched. Need....better....job.


Be careful about that pipe, looks like it'll be slung proper low.
____________________
KAWASAKIIIII

[binge]

The main reason I've fitted the pipe like that is to keep it unmodified.
I had trouble jetting the TZR pitty because it had a bastardized pipe on it, from a very early pre-powervalve DT, which had been cut and re-welded to fit. This, in-turn, messed up the running all together.

This pipe, is a pre-cat system, and all I have done is shorten the stinger pipe by a few inch, so it should still run spot on.

My only issue is going to be the lack of air-box.

[SQL]

[binge]

Photo is quite deceiving too.
The pipe work (Lowest point anyway), is fairly in-line with the wheels/tyres.
So any cornering etc, wont actually bring the pipe any closer to the floor.
The only thing I'll need to be careful of is big speed bumps.

But then, my other bike is this, so I'm kinda used to it :p

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-prn1/993506_10152086516485606_787575319_n.jpg

[stevo as b4]

The only thing I thought that might help, but would still need a lot of modding to fit would be an Aprilia MX125 pipe, if you found one laying around?

[binge]

Thought about that. But it's the modding of the pipe I dont want to do.
Plus, having the pipe underneath gives me more room around the engine, for things like carb / airbox / battery etc...


Today I did do:


Downloaded Photoshop

Found a crack to unblock it (I'm a cave man with technology so quite proud of myself there)

Then I worked out how to use Photoshop


And then I designed these:

https://scontent-a-lhr.xx.fbcdn.net/hphotos-prn2/t1/1555301_10152123972760606_279487124_n.jpg

[binge]

Nothing of any huge interest.

Fitted the Montessa yokes as they sit about 1/2 inch wider than the pit bike ones:

https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-frc3/t1/1604656_10152132870930606_1533332840_n.jpg



Got a Ducati 748 rear shock on the way to see if it'll work well with the bike.
Then it's coming to work with me. One of the fitters in the De-pollution shed is going to weld it all up for me. I have trust in his work, as he re-tips the jaws on our grabs for a living:

https://i45.tinypic.com/1zq62d1.jpg




Ben

[binge]

Right then...

https://scontent-a-lhr.xx.fbcdn.net/hphotos-prn1/q83/s720x720/1012688_10152133847940606_638675829_n.jpg


https://scontent-a-lhr.xx.fbcdn.net/hphotos-ash3/q81/s720x720/577365_10152133847860606_620531533_n.jpg

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-prn1/t1/q81/s720x720/1532052_10152133847735606_1787910022_n.jpg

https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-prn2/q79/s720x720/1526877_10152134909420606_605072903_n.jpg

https://scontent-b-lhr.xx.fbcdn.net/hphotos-prn2/t1/q77/s720x720/1520822_10152134909575606_81763823_n.jpg



Epic Granddad is Epic!

[binge]

It's starting to take a bit of shape now.
Tank shrouds need messing with.

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-prn1/t1/1017401_10152142319250606_1428989648_n.jpg



Ben

[binge]

Spent the evening getting the engine somewhat built.

https://scontent-b-lhr.xx.fbcdn.net/hphotos-ash3/t1/q77/s720x720/1546001_10152162018050606_47023682_n.jpg


https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_191643_HDR_zpsa2d73d27.jpg?t=1391207734

https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_203911_HDR_zpsb2d9bbbd.jpg?t=1391207767

https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_211358_HDR_zps4d1f8cef.jpg?t=1391207840

https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_211403_HDR_zps163c8dcd.jpg?t=1391207801

https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_211411_HDR_zps80965650.jpg?t=1391207874


Now this is where I'm a little confused.
Top left of the flywheel. Gap appears to be for a crank sensor of some sort.

https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_211504_HDR_zpsdff1c390.jpg?t=1391207910


But looking at the threads, it's clear I defo did not take anything out of here.

https://i902.photobucket.com/albums/ac227/pitbikeben/20140131_211518_HDR_zps85123ed4.jpg?t=1391207941


So it either doesn't have anything there, OR, it was taken out before I got the engine, and that lower bolt hole has taken a knock.


Any ideas?



Ta



Ben

[Kickstart]

Hi

That is a 123 engine which normally had the SEM ignition.

The later 122 used a different ignition system which did use a crank sensor (mounted about there). Have heard that there were some 123 engines using the later ignition but not seen one. Presume they just cast the late cases to take both.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[binge]

Cheers Keith!

Bought a PV blade online, all I need now is a servo and cable, then it should all work, as I already have the control module.

I was going to convert over to the Kart setup, but it's a lot to lay out as I need to change everything. I'd also need to drill the barrel for the air port.
Maybe something to consider for the future. It would of been a better option for a track bike really as you can adjust the PV.

Also ordered a circlip for the sprocket. Didn't realize it was on one, I thought they bolted on.

[Kickstart]

Hi

Both power valves have their plus points. The pneumatic one is simple and can probably be freed off in a few moments after just popping off the cover, but it does seem more prone to sticking.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[TwoWheelsDail...]

Any updates?
____________________
Suzuki GSR 750 - 33BHP (Restriction Ends 17/12/2014)
KTM Duke 125 - SOLD
www.facebook.com/TwoWheelsDaily | www.twitter.com/TwoWheelsDaily | www.instagram.com/TwoWheelsDaily

[garth]

Nice progress, although I think your taste in spray paint is a bit dubious!

Itching to get back on my pit bike.