Building a race bike

With regard to the sub-sump, my thoughts go to gearbox lubrication. Something extra needed to provide that? I'm assuming the oil 'level' will now be lower than standard. Will splash take care of it? In my minds eye I can't remember if the gears touch the standard oil level.
 
Good point, Haggis... I assume the gearbox will be closed off from the other oil by closing the passages. This way you could maintain different oil-levels and even different oil viscosities easily... For that though, one would need a new hole for draining the gearbox... :unsure: or simply take off the shifter cover to drain the gearbox oil?!?

Hope the ground clearance is big enough to avoid touching ground when the bike fully compresses, but I think that was encountered.
 
Haggis said:
With regard to the sub-sump, my thoughts go to gearbox lubrication. Something extra needed to provide that? I'm assuming the oil 'level' will now be lower than standard. Will splash take care of it? In my minds eye I can't remember if the gears touch the standard oil level.
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Yes, original the gears will touch the oil. There are 2,2 cm from the bottom to the end of the (screwed in) dipstick + 2,2 cm from end to the upper oil-mark + 9 mm effective thread (difference screwed in to put on) = 5,3 cm total oil-level in the 750 gearbox.

Thomas aus LAU
 
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Transmission and crankshaft lie horizontally in one plane. If the transmission gear wheels touched the oil, the crankshaft would, because of the greater OD, foam up the oil - or am I thinking wrong here?

Where actually is Cam? His analytical skills are sorely missed right now ...
:cool:

Cheers,
Jo
 
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That's why windage trays are used, so will the oil lever height be the same as std relative to crank and gearbox height in the case but have more capacity. I think it's a plane bearing crank and hi-pressure oil pump as said earlier.
 
Jo said:
Transmission and crankshaft lie horizontally in one plane. If the transmission gear wheels touched the oil, the crankshaft would, because of the greater OD, foam up the oil - or am I thinking wrong here?
Where actually is Cam? His analytical skills are sorely missed right now ...
:cool:Cheers,
Jo
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The oil splatter sheets under the crankshaft are fixed at a height of 6.8 cm. So we will have more a splish-splash-situation in the gearbox. In curves depending of the speed, the gears may particulary have direct contact to the oil-level and throw oil onto the gear wheels.

Thomas aus LAU
 
The oil level will stay essentially the same level as Vince said.
The crank and gearbox will both have specially designed scrapers to remove as much oil as possible from each and the oil directed into the sump and baffled to keep it there as much as possible.
I will use the same oil as I want to cool it and use it for both lubrication and cooling, one pump two coolers, one main sump one sub sump. Lots of baffles and scrapers etc. Lots of head scratching. But I have a cunning plan Mr Blackadder.

Just fitted it all up and have 120mm ground clearance between the exhaust and floor. Am happy with that as the BMW K1 in my showroom has the same ground clearance and an R1 has 130mm so about close enough to call the same. And an R1 will bank a lot further probably!

Pics tomorrow.

Regards,
Jules
 
Separating gearbox would require sealing the LH main and layshaft bearings and a few other bits and pieces. Irrelevant anyway, as Julian has pointed out.

Julian does your clearance calc factor in the width of the sub-sump? Just wondering if the sides of the sub will touch before the 120mm clear exhaust under severe lean angles.
 
Hi All,
A few pics taken late last night, Lean angles won't be an issue, I have put a straight edge up from the bike centre line and the crankcase hits well before the exhaust or sub sump come near, its quite sleek as you can see so not a big wide lump. (volume is 1.65 litres)
Nice thing is that with the sub sump on it means I can make my primary pipes exactly the correct length that I need and still keep them simple. And it gives me a perfect run for the perfect length secondary pipe coming up between the swing arm and the frame and out on the side.
The pic of the whole bike is at ride height with both wheels on the ground.
 

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Quick everyone, buy stocks in a cotton-bud manufacturing company. Julian is soon going to buy-up the world's stock to clean all those lovely holes. :)

Thanks for keeping up the posts Julian - a good read and very interesting to follow.

As it is a racer, do I take it there is no thought of oil filtration - that duty taken simply by having fresh oil at all times?
 
Hi,
No, it will have a gauze screen to stop blowup parts going into the pump but no filter. it will have fresh oil every single race without fail as this is a very good indicator of what is happening inside the engine. 30 euros to know that information is a very good deal.
and it would weigh too much anyway :D:ROFLMAO::D:ROFLMAO:
J
 
Here it comes, what oil will you run. Any thoughts on Castrol R, or has that gone the way of the Dodo. How about your Race Cars as well. A mate used to run it in his GT Bevel, yep gumming and seepage issues and all. He reconded on zero wear, I liked the smell following him.
 
Yes, we had that discussion. The first time I saw it, Motul 300v for sale in oz it was $140 for 4 litres, double its competitor's price and my jaw dropped, I couldn't believe my eyes.
 
Vince said:
Yes, we had that discussion. The first time I saw it, Motul 300v for sale in oz it was $140 for 4 litres, double its competitor's price and my jaw dropped, I couldn't believe my eyes.
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Then again, you can leave it in there twice as long and use it in your car when you drain it from the bike.

Paul
 
Jo said:
Transmission and crankshaft lie horizontally in one plane. If the transmission gear wheels touched the oil, the crankshaft would, because of the greater OD, foam up the oil - or am I thinking wrong here?

Where actually is Cam? His analytical skills are sorely missed right now ...
:cool:

Cheers,
Jo
Click to expand...
Both the crank and gearbox gears are well above the oil level. 'box is splash lubed by fling-off from the crank out of the big-ends, supplied through 2 windows (twin) in the seperation between gearbox and crank compartments, immediately behind the crank webs. The windage trays prevent oil sloshing to the front under heavy braking. Probably no great problem in itself in regard to oil drag, you're not needing much engine power when hard on the brakes, but would probably cause excessive smoking because a lot of oil would find itself being forced up the cylinders by the spinning crank.

Anybody that has experienced wet-sumping in a dry-sump engine knows what oil drag feels like. Worse on a crank than a gearbox, but highly undesirable, all the same. Oil level in seperate brit-type gearboxes is so that when everything is spinning, none of the gears dip in the pool on the floor, the oil picked up after take-off being flung all over the place and being held in "suspension" as long as the gears spin. When stopped, the lower shaft, usually layshaft, is up to the centreline in oil (Norton/AMC).

piet
 
I've been a convert of Mobil 1 for decades. Proved high class oil. Never had a clutch prob with the std version but new motor will use the wet clutch friendly version once run in on 20/50 mineral.

Love the assembled pic Julian - can see the shape shifter coming out!
 
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