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Crankshaft seal for supercharger
richard thomas - 19/5/07 at 07:54 PM

Just read a thread on supercharging and a thought struck me...

How does the take off shaft from the crankshaft get sealed for oil retention as it passes through the end cover on a bike engine?

[Edited on 19/5/07 by richard thomas]

[Edited on 19/5/07 by richard thomas]


mark chandler - 19/5/07 at 08:33 PM

On blade engines the charger replaces the water pump you then replace with an electric water pump.

rgds mark

[Edited on 19/5/07 by mark chandler]


richard thomas - 19/5/07 at 09:04 PM

Thanks,

Anyone know the score for a 'busa engine?


bike_power - 19/5/07 at 09:14 PM

The end cover is machined (by TTS) to accept a bearing and an oil seal.

I believe the crank can be damaged without the bearing being in there. Some people tried using the same type of drive as Westfield use for their oil pump but an oil pump only needs a few bhp but supercharger can take 30 or 40.


richard thomas - 19/5/07 at 09:35 PM

Makes sense...I suppose the shaft drive simply screws into the end of the crank? I'm trying to recall how mine looked when I fittd the extreme starter cover but I can't remember.


bike_power - 20/5/07 at 07:11 AM

I forgot to take some pictures of mine but there's what looks like a large top hat with 3 pins in it which locks into the 3 holes in the starter clutch drive on the end of the crank, the cover slides over the shaft of the top hat and the sc drive pulley is put on the end of the shaft, then a long bolt goes through the whole lot.

The drive is provided by the three pins rather than the bolt, the bolt simply holds the whole lot onto the end of the crank.

Some things you can buy for bike engines are not perticularly well thought out or made but TTS really have done a good job with this, it's well machined, fits perfectly and is absolutely spot on.

They might sell you the bits if you ask, speak to Richard.


richard thomas - 20/5/07 at 09:13 AM

Thanks for that, I might just give them a ring....

Fancy doing a home grown job - more for something to do than anything else but there are some things that are just too difficult/risky to manufacture. Also don't fancy splashing all that cash out either although I reckon a DIY might end up more expensive in the long run....


bike_power - 21/5/07 at 07:11 AM

quote:
Originally posted by richard thomas
Thanks for that, I might just give them a ring....

Fancy doing a home grown job - more for something to do than anything else but there are some things that are just too difficult/risky to manufacture. Also don't fancy splashing all that cash out either although I reckon a DIY might end up more expensive in the long run....


I think you're right, TTS have kept it sensible and made the right bits for the right price, given the amount of development that's gone into it.

If you get it wrong, the nose of the crank could snap off - if that happens at revs then the pistons will carry on up the bores and smack the valves which by then will not be moving because the cam drive is on the nose of the crank that's snapped off !