Hello again,

Refering to my 64mm stroke crankshaft in my 325 sherpa t engine, that should be a 60 mm stroke. Am I disappointed after fitting a new rod kit and assembling the engine cases.You better believe it I am. Should I have checked the stroke? Maybe I should have.But in my defence I bought it as a basket case.

Well I have a Italjet 326cc engine spare sitting on a bench in the shed.Does anyone know if the crank out of it will fit my Bully.I know they share common piston's and rod kits.They have the same flywheel.They share the same bore and stroke.I guess I could strip the engine ,but the work benches are full at the moment.

So if you can help it would be appreciated. I'm on the look out for a crank anyway.But if the italjet one will fit I can just use it.

Thanks again.

Brian

Hi Brian,

I was thinking about your bike as I was in the shed, fettling the Beesa. You can use a 250 Bultaco crank (or better still a 325), but needs the 325 rod as the little end is bigger. I don't know if the Italjet will fit, measure it up, same stroke? I don't know if the Italjet has the same taper for the mag (wouldn't think so) and if the Bult sprocket and weights could be adapted to fit the Italjet crank.

Another semi useful thought to get you going and not have to machine anything or ruin any parts, you could drop out the sleeve from the barrel (upside down over a ceramic plant pot in the oven when your wife is out), then machine up a 2mm thick spacer to slot inbetween the liner and barrel, like a big washer and re-fit in the oven.

This theoretically provides you with the correct port heights and piston crown height without having to machine any original parts. Although the liner and cylinder ports would mismatch, it shouldn't affect performance too much.

Alternatively, make up a base spacer - actually this is much heasier and gives the same results as above. Or get hold of an Alpina cylinder and head.

Bye, PeterB.

Hello peter,

The italjet runs the same flywheel.

I like your idea of using the oven when my wife goes out. But wait there's more.There is a 325 crank on UK ebay.But he only ships in the UK.I have a Uncle over there.I'll contact him tonight and see if I can ship it to him and he can ship to me.That sound's easier.

If I stay with this stroke and fit a pursang barrel I'll have 356 cc's. Run a under bike expansion chamber and 38 mm mikuni. Look out hill climb's.

On a more serious note.I'll get the correct crank. Just seems easier. Funny enough though my mate and I compete against each other in twin shock trials. I bought the italjet first and he got a 158 sherpa 250.He rode my bike and liked the 350 power. He then bought a 199a and a 198a.

Then I bought the 159. So he bored his 199a to .75mm over.So I went 1.0mm over.So really it's getting to be a size thing.Mine's bigger than your's. So if I leave the 64mm crank in I win.

I'll keep you posted and see where I end up.I like your idea's though. The spacer under the cylinder leaves the ports intact, but does mess with the cylinder timing.

Can anyone tell me/us what will the effects be on the bike with the intake opening 2mm later and exhaust closing 2mm later.It doesn't sound right but hopefully someone will get what I'm on.

Thanks again

Brian

Hello peter,

The italjet runs the same flywheel.

I like your idea of using the oven when my wife goes out. But wait there's more.There is a 325 crank on UK ebay.But he only ships in the UK.I have a Uncle over there.I'll contact him tonight and see if I can ship it to him and he can ship to me.That sound's easier.

If I stay with this stroke and fit a pursang barrel I'll have 356 cc's. Run a under bike expansion chamber and 38 mm mikuni. Look out hill climb's.

On a more serious note.I'll get the correct crank. Just seems easier. Funny enough though my mate and I compete against each other in twin shock trials. I bought the italjet first and he got a 158 sherpa 250.He rode my bike and liked the 350 power. He then bought a 199a and a 198a.

Then I bought the 159. So he bored his 199a to .75mm over.So I went 1.0mm over.So really it's getting to be a size thing.Mine's bigger than your's. So if I leave the 64mm crank in I win.

I'll keep you posted and see where I end up.I like your idea's though. The spacer under the cylinder leaves the ports intact, but does mess with the cylinder timing.

Can anyone tell me/us what will the effects be on the bike with the intake opening 2mm later and exhaust closing 2mm later.It doesn't sound right but hopefully someone will get what I'm on.

Thanks again

Brian

325 with a pursang barrel who would be man enough for that beast (?)!!!

325 with a pursang barrel who would be man enough for that beast (?)!!!

Apparently not that unusual.

It's ridable, but you'd better know what you are doing.

325 with a pursang barrel who would be man enough for that beast (?)!!!

Hello Nigel,

Sound's like a dare to me. Get me a pursang barrel and I'll do it.Then we can see if I'm man enough to hold it.

Thanks

Hello Nigel,

Sound's like a dare to me. Get me a pursang barrel and I'll do it.Then we can see if I'm man enough to hold it.

Thanks

Martin will tell you what its like!

Hi ,Just a thought to use with the 64mm crank. The model 213 Alpina has a 64mm stroke and a 83.2 mm bore, as listed in my 212,213 owners manual.Might come close for Trials bike port timing.. Dean

Using the (64mm stroke) Alpina crankshaft and top end is a common mod for people who want more grunt than a 325 Sherpa T provides. The Alpina port timing and compression ratio is fine for trials.

My Alpina 138 is an overbored (360cc) 64mm stroke motor and the performance is quite refreshing on big hills - even with the standard 27mm carby and exhaust.