Single TM42 Carb

[basser23]

Hey all, anyone try the single TM42 carb kit that was available through
Bikeworx?
I have been in contact with Bill Jurgenson in Germany who builds Mz
Skorpions, and he uses this carb on a 60hp Skorp..I understand it is
an easy upgrade.

Thanks
Chip

[Jimbo]

Hey, I have the 42 mm single carb kit on my skorpion along with a 2 mm overbore high compression piston (686cc), mild megacycle cam and an M4 exhaust. It runs strong but sucks a lot of gas compared to my other skorpion I had with the rejetted stock carbs and an exhaust. I also went up one tooth on the front sprocket (16). Jimbo

[basser23]

Jimbo,
I would expect the modded motor to use more fuel...curoius, did the
686 pull so strong that you could up the front sprocket a tooth and
have improved performance? My Skorp runs a 15/42 combi,the acceleration is quick,but 1st gear is WAY short.....
I would like to mod my motor the about the same as yours this winter.
Where did you get your work done? Did you farm out / or buy a new cylinder and piston? Are you running the stock header....arguably not the
best with a modified engine...Bill Jugenson(Germany) recommends at least
the Euro Sport Cup exhaust made for the series over there...of course it is
no longer available..that 2 into 1 exhaust has 34mm pipes into a 56mm
diameter piipe...possible to duplicate with a good fabrication shop....Tunebike had some 2-1 exhaust developed also....
Thanks
Chip

[Wonky]

We can supply you with 2into2 race exhaust system for £575 and a longer first gear for £99! The standard head is fine with port and polish work, depends on what stage you want it! Our bikes put out tons of bhp!

[Wonky]

Best carbs are the Keihin CR's, they are kick ass carbs and will wipe the floor with anything else on the XT660!

[Jimbo]

Hey, I bought my present skorpion from Galen Miller at Bikeworx. He did all the work on the motor and told me there is more power to I can get out of it, but would need to put in a Carillo rod, which is the weak link in the motor. I think for the time being I'm going to do some brake and suspension upgrades and leave the motor as is for reliability reasons. I went up one on the front sprocket for a track day at VIR (north course) and liked the way the bike ran so I decided to keep it on for everyday riding - which consists of fast country roads with a few sweepers. The gearing is fairly tall - and I know the speedo is probably not acurrate - but I can hit 65 mph in 2nd gear, 80 something in 3rd, around 105 in 4th and 5th is like overdrive taking a while to get up to 115 - 118 mph.

[Jimbo]

Hey, I bought my present skorpion from Galen Miller at Bikeworx. He did all the work on the motor and told me there is more power to I can get out of it, but would need to put in a Carillo rod, which is the weak link in the motor. I think for the time being I'm going to do some brake and suspension upgrades and leave the motor as is for reliability reasons. I went up one on the front sprocket for a track day at VIR (north course) and liked the way the bike ran so I decided to keep it on for everyday riding - which consists of fast country roads with a few sweepers. The gearing is fairly tall - and I know the speedo is probably not acurrate - but I can hit 65 mph in 2nd gear, 80 something in 3rd, around 105 in 4th and 5th is like overdrive taking a while to get up to 115 - 118 mph.

[Jimbo]

Hey Chip, The Keihin CR carbs are what most of the racers are using but very expensive. What are you going to using your bike for? I'm having alot of fun doing some track days - you can hear my bike coming from a mile away compared to all the inline fours on the track. I'm still using the stock head pipes. There is a limit on how much money I want to put into a single cylinder sport bike that all my buddies devour on the straights! If you're going to race it - you can do a ton of stuff to that motor. Jimbo

[basser23]

Jimbo,
I use my bike strictly for the street right now..I am fully aware of the FCR's and their astronomical $$$$$!
If you recall back the day there was a series for the Skorpion that was run
at CCS and WERA races. My bike belonged originally to a racer in the midwest, and is still set up to be legal for the "Cup" series. Basically stock with a re-jet and Holeshot can. Clip ons'...yadda yadda...
The mods I'd like to do are: Higher compression piston, TM42(or BST33's
from a Raptor) a stage 1 cam, and more effective exhaust..while retaining
the side stand (center stand is missing).I figure also a polish and port cleanup..this should get ABOUT 60hp which is perfect for my purposes.
I know these motors can produce much more, but I don't need it......
If you know of a good exhaust fabricator let me know...2 into 1 will
work fine...again 2 into 2 out of the question due to side stand issues
thanks
Chip

[Wonky]

Our guy makes a 2 into 2 system that custom fits with the stand still fitted!!!

[basser23]

Wonky,
Tell me more about that dual system...my step son lives in Bromley
and could possibly ship / pick up in Seven Oakes.
Thanks
Chip

[Wonky]

The 2 into 2 systems we use on ALL our race-bikes, "Cookie" exhaust systems, they work fantastically and Cookie is a talented guy with years of experience. You can have Aluminium or Titanium casings on the cans. He has made exhausts for tons of MZ, SZR's and so on. We are actually based in Sevenoaks buddy. Bromley is just up the road from me. I would need to know if you are running the side-stand,etc so Cookie could make your system for you. He actually likes to take the bike away and custom fit the sytem to fit your bike, this is a great way of ensuring an absolutely snug fit. I can arrange it all for you if your in need of a system. The bike pictured above boasts Cookies exhausts, that was on a test day at Brands Hatch a few weeks ago, Whysub was there too. Any help i can give you is here buddy, just ask. We have started to list MZ/XT parts on our online store now, custom parts will be there soon too.
https://teamslipstream.co.uk/sos

Hope this helps!!!!