Bimota Forum

[Corona]

Bloody old jap motors always something JK


I'll just get my coat then

[oily]

Bloody old jap motors indeed

Anyway..........
Drained the oil, amazing what a few minuets of steam will do to £25 of new oil



Off with the lid......
Full of mayonnaise



Top of the head.....



Head off.......to find it's blowing well between 1 & 2 and the water jacket.
Bloody good blow too. Looks like this blew from the minute it was built




Barrels off to find...........

78mm JE pistons......as new. So it's been over bored by 2.5mm





Spoke to the Yorkshire god of all thinks big bore and he says these engines do not like big bore's. Oh dear. Anyway, I'm sending the barrels up to him to be decked and checked over.
I'll give this motor one more chance

[Pompey]

Well done old fella! Might be an idea to put new rubber bush in the charging system whilst the engines out? RF900 will do it
_________________
Pomps
Bimota's Db2, Db5 ,Ducati's 851' 92, 888' 93, Honda blade' 93, Triumph speed triple' 07, kawasaki zxr 750 k1

[oily]

[Evilchicken0]

2.5mm over is new liner territory, it could be the new liners haven't been set completely true so causing the blow across the cylinders first, then it worked it's way across the gasket until it did the water jacket. The piston crowns look clean so I'd say it hasn't seen many miles.

Could be a nice find, if it proves an easy fix.

Did you drop in a heavy duty clutch ???
_________________
Don't read everything you believe

[oily]

That's exactly what I was thinking with the liners but after doing my homework, 78mm is the biggest you can go on standard liners
I'm getting the barrels decked to eliminate that.
I would say the pistons (JE forged ) look like they ain't done 100 miles.
If it all works, then..............RESULT

[Pompey]

How about new front sprocket ( 1 tooth down from original )... Saves another drop in the future?
_________________
Pomps
Bimota's Db2, Db5 ,Ducati's 851' 92, 888' 93, Honda blade' 93, Triumph speed triple' 07, kawasaki zxr 750 k1

[Evilchicken0]

Better to go up on the back, you won't strain the chain so much. might get a bit frisky if you drop the gearin to much though
_________________
Don't read everything you believe

[oily]

Pompey, In this instance, due to the theoretical extra power and torque and the fact that the front sprocket looks new and I'm a cheapskate, I think evilchuck is right and any tweaking of the gearing can be done on the rear sprocket. Good thinking all the same

[Corona]

I would consider camchain and tensioners depending on condition myself also a check of the big ends and main bearings. Are there any metal filings in the oil? A good check is a magnetic screwdriver swirled about in the oil, this can reveal any ferrous particles, this trick is also handy for any considered purchase of an engine. I use a piece of magnetised wire gently pushed into the oil via the filler cap, if there is a small hedgehog on the end of the wire, walk away. Using good quality gaskets for the rebuid like Cometic http://www.cometic.com/gaskethome.aspx I have used these on drag bike motors bored out to nearly 1500cc, don't know if you can go that far on liquid cooled motors, they are good and they can make any size to suit.

[oily]

Just had word from the engine tuner............
His initial view is..............I might be better orf going back to standard barrels and pistons
He's going to measure and inspect everything properly, soon and get back with his verdict.
I might spend the waiting time looking for barrels and pistons, check out the WANTED section

[Evilchicken0]

Not great news, but this engine tuner doesn't like the 1100W being tuned anyway so it's not an altogether surprising response.

Is there something wrong with a componant part - if not is it a problem with how it was built ??? If not that then it's an inherant problem and will always blow gaskets which is odd because these engines go straightline racing even if they are modified.

Your allowed a second opinion.
_________________
Don't read everything you believe

[oily]

My engine tuner agrees with you totaly.
He say's these engines, big bored, make superb straight line, short burst engines but not reliable road engines

I'll see what he says about the condition of my block and then maybe explore having new liners pressed in

[oily]

UPDATE.........

Barrels have been honed and decked and are on their way back. Apparently they were bored a thou too small anyway
2 thou taken off the top to make sure they are flat.

cylinder head being skimed as we speak

Ordered a head gasket at 16:00 hrs yesterday and the postman got me out of bed this morning to sign for it. A big well done to Eastwood racing and Royal mail

Getting all excited, the engine should be back together this week

[oily]

Barrels... Honed and decked by 2 thou
Head...4 thou skim which was the bare minimum to get it flat.
Now ready to get this thing back together and back in the frame (again)



Almost a shame to put a head gasket between them