Engine Blown Out!!!

I bet you do! If they sell motocross bikes, there are people who rebuild single cylinder crankshafts. It's actually a crude press to get it apart but just a specific jig to line it all up again and a really simple device to make sure it's balanced. And if a crank builder says he won't work on a scooter crank he's just an asshole. Go to your nearest yamaha dealer and ask who does their crankshaft rebuilding. Someone does it. I know a vietnamese guy that does it with just the press and lines it up by eye and his lambrettas are fast as all hell!
 
Mexicano said:
Emo:

Just I guess a press is needed but how to align it again in the same position? Is an special tool needed?

well, here a sharp eye sight, a hammer & a leveled crankshaft holder will do to align the crank.. its so hard to elaborate it here on how they do it, it really effective..
 
my brother replaces conrods & aligns cranks all the time & he does it pretty well using a hydraulic press stand with a crankshaft holder, he has this method of aligning it & it's so effective that it doesn't vibrate at all. he spent hours practicing on dummy cranks before he mastered it but i sure do love to get my hands on the crankshaft alignment stand.
 
i have seen people here that race malossi bikes for the local track here take a mhr team crank and get it "trued"(as we say) or aligned better..it does help alot but i neve did it...i wanted to but the guy locally who used to do it is done now.
 
Lilplaya: That process is known as "blueprint", almost every professional race engine builder (At least in 4 stroke) carefuly balance "by hand" their parts.
 
O.K. my new cylinder and piston is ready to be mounted again.

HERE YOU CAN SEE THE SMALL "LINERS" THAT GOES INSIDE THE PISTON TO REDUCE FROM 14 M.M. PIN HOUSE TO 12 M.M. PIN

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THE LINERS PRESSED INSIDE THE HOUSINGS

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THE MODIFIED PISTON, THE NEW 12 M.M. PIN (SPECIALLY FABRICATED) AND THE TEFLON BUTTONS

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Speed: I will re-bore the old cylinder and re-plate it with Nikasil,get a 58 m.m. Wiseco piston sooner, I also will port the exhaust port a little bit more and keep this new set as a spare.
 
New cylinder is ready:

STOCK EXHAUST PORT...AS IT CAME FROM MALOSSI
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AFTER SOME PORT JOB
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Almost ready to be up and runing again!!!!!

Still waiting for my new Yasuni Carrera 21 pipe to make some test.....
 
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Mexicano said:
New cylinder is ready:

STOCK EXHAUST PORT...AS IT CAME FROM MALOSSI


AFTER SOME PORT JOB



Almost ready to be up and runing again!!!!!

Still waiting for my new Yasuni Carrera 30 pipe to make some test.....

Why didn't you buy the 123 cc Polini alu cylinder instead of the Malossi cast iron?
 
Browni:

Are you talking about the Art.-No. P1660075 (Sip-Scootershop)????
No one told me the Polini 120 c.c. was aluminium!!!!...maybe next time...

Thanks!
 
C30? isn't that too much for a tricked out Malossi 57,5mm kit? that stroker won't see the revs where the C30 was made to run at, for your kind of set-up i'd look into those pipes made by the japs called WJ (windjammers) 'coz the BW'S100 motor is very popular in japan in 50m sprint races they punch up the displacement to 132 using a 57,5mm kit & a 53mm ruima crank.
 
Tiba: Thanks but I can't get those Windjammers...fucking japans never answered my e-mails.....I will try first the Carrera 21 and if doesn't work O.K. I will go for the Gilera JollyMoto for 125 c.c. and modified it for my minarelli engine.....research and development mate....no other way.....

If the Yasuni doesn't work I will sell it here...only problem would be the shipping cost.

Reagrds,
 
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Mexicano said:
Browni:

Are you talking about the Art.-No. P1660075 (Sip-Scootershop)????
No one told me the Polini 120 c.c. was aluminium!!!!...maybe next time...

Thanks!


I thought you know it..

Yes I meab that code number- > Polini 123 cc NiKaSil plated cylinder

I tried a 100 cc Aerox with this cylinder+Tecnigas RS and it was quite fast, sure this is not a high reving cylinder it has got a very low port timing!
 
Mexicano said:
Tiba: Thanks but I can't get those Windjammers...fucking japans never answered my e-mails.....I will try first the Carrera 31 and if doesn't work O.K. I will go for the Gilera JollyMoto for 125 c.c. and modified it for my minarelli engine.....research and development mate....no other way.....

If the Yasuni doesn't work I will sell it here...only problem would be the shipping cost.

Reagrds,


I think try out that C30.. Sure it's a high reving pipe, but works different on different bikes!
 
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