big block XS250 (400) Turbocharged

I see a lot of guy removing the squish band as a performance upgrade:confused: Why I don't know maybe to lower compression. I know decking the head and adding one will make more power I have had it done on some two strokes.


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I thought so but I have seen people do this on a non-turbo engine. :shrug: What ever make them happy:laugh: Can't what to see how your turbo turns out. Will you be putting it on a dyno to see what gains you have gotten?
did this this morning

Havnt even put a screwdriver to the carbs or points yet, It runs like a dream Decided on 27.5 pilot and 190 main see well see how that goes

Spent the rest of the day stuffing arount with petcocks trying to bypass the vacuum shut off as these carbs dont have a take off point and i still didnt get it finished.

Anyone know of another model i can get one off?? otherwise it will be 2 in series

Then off to get registered


No Turbo? Or will you do that later. Its nice to have them start and run good after all the work you put in it:thumbsup:
I'm trying to use the original untill I pull it apart and clean it up to put the turbo on because it matches the side covers but that's the one with the problematic petcock.

The jetting feels close, it's really responsive.
Give me a brake!!!

Went to go on a test ride....... clutch works, shifts into gear. Crusing down the side of the house and went to slow down to negotiate the small gap between the bins and.... no front brake..... no rear brake. after crashing into the bins I weeled it back around the back. seemed to have a little pressure and I thought it would free up but they are locked solid so I pulled it all off and apart


Lots of crusty crap in both calipers and both lines were blocked so I has new ones made


Stripped and cleaned the rear master twice as it was filled with custard but couldnt get it to bleed so the old man knocked me up this


It worked a treat straight away with a hand pump.

Fitted my XS650 reed valve breather


Got my fancy Lithium battery that feels empty


And were away. Rides good, brakes good.
Pilot is spot on, main is miles off... Ill but 140s and try again

Went and saw this thing for inspiration, looks unreal in the flesh

no been flat out with work and still havnt gotten it running well enough to register

Plus have been doing this


Wrecked one figuring out how it comes apart, Ill write up an artle for anyone else who wants to do it
Not really, going backwards.
Those carbs are a piece of poo so Ive filed them in the nearest trash receptacle and are adapting the flatslide TM28s, currently getting adapters laser cut. Dont ever contemplate buying knock off Mikunis cheap on Ebay, they may be cheap but they are cheap and nasty.

Plus Ive been silly and purchased 3 more bikes including a Rickman CR900

Ive just started renting a corner in a fully equipped mechanical workshop so should get some decent progress soon
Ya I have never seen one over here in the states. Then again, I probably wouldn't have know it if I did.
write it up, gotta fix mine, it dances all over the place.

and next time your brake goes out, use your engine as a brake by downshifting and gently easing out your clutch, and I mean GENTLY.