Topic: CB750 Wet Sump Conversion - Sumpthing

[Bert Jan]

The chopper guys would probably be glad to get their hands on one of these. No more hassles with locating the oil tank on the frame with extended lines. It would give a much cleaner look.

Stick with what you're doing. Sometimes this forum can be brutal when in my opinion its just not necessary.

Agreed👍

George

Thanks guys, appreciate it!

[kmb69]

.....At this particular time, we're 2 kits short to order in a new batch. That's no marketing blabla, it's just how it is.

So if I order 2, how long to get them?

[Bert Jan]

The next batch will be here in about 2/3 weeks. Shipping to USA is anywhere between 6/12 working days. Thanks for your interest btw!

[Bert Jan]

We're also working on a USA dealersystem, so could be a bit cheaper (less shippingcosts) if you order from them later on. No idea how long this will take though

[Medyo Bastos]

Looks great! Guys, us chopper guys usually have ground clearance issues. How much lower do these hand below stock?


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[gschuld]

I believe the number is 50mm(1.96”)

George

[voxonda]

Correct George, 50 mm.

[gschuld]

And FWIW, I just measured a few things down below the bike.  The lowest point on the kickstand bracket below the frame rails is 2”.  The bottom of the factory oil pan is almost perfectly even with the bottom of the frame rails, with the drain bolt hanging a further 1/4” or so.

So with the Sumpthing wet sump system mounted in a factory chassis, the bottom of the 2” lowered oil pan will be dead even with the lowest point of the kickstand bracket, with only the oil drain bolt dropping down a tad further.  The 1978 cb750f factory 4 into 1 header, for example, hangs lower than this.

George

[voxonda]

Think you mean side stand bracket, George?

[gschuld]

Corrected above🙄.  Thanks Rob, my brain has questionable function after going to the gym.

George

[kmb69]

The next batch will be here in about 2/3 weeks. Shipping to USA is anywhere between 6/12 working days. Thanks for your interest btw!

Just placed an order for one.
Keith

[Bert Jan]

The next batch will be here in about 2/3 weeks. Shipping to USA is anywhere between 6/12 working days. Thanks for your interest btw!

Just placed an order for one.
Keith

Order is received, thank you!

[voxonda]

While waiting for some oilpump parts, gaskets and bolts, I removed the oiltank and lines. Bike looks a lot lighter now........

[Tintop]

It will be interesting to see how moving the weight of the oil & tank, and putting it under the engine changes the centre of gravity, and if that requires slight suspension setting changes.  Should put slightly more weight on the front end.  Following with interest Rob.

[voxonda]

It will be interesting to see how moving the weight of the oil & tank, and putting it under the engine changes the centre of gravity, and if that requires slight suspension setting changes.  Should put slightly more weight on the front end.  Following with interest Rob.

Hey Brian, thanks for your interest. Shifting weight up front and down low will change the C of G just very slightly and I do not expect to have to change my setup. Need to build new pipe because of the low sump, so maybe even have to raise the whole bike a little bit..........

Cheers Rob

[slikwilli420]

How much does the kit weigh? My aluminum oil tank with all fittings weighs 42oz. I will have longer oil lines but that will add another pound at most. That thing looks pretty heavy.

[voxonda]

How much does the kit weigh? My aluminum oil tank with all fittings weighs 42oz. I will have longer oil lines but that will add another pound at most. That thing looks pretty heavy.

This "thing" weighs 46oz.

[voxonda]

I do cause of cooler, but no lines on streetbike, correct.

[slikwilli420]

Ok so probably a 1lb savings over an aluminum oil tank. Not bad. Watching with interest.

[gschuld]

For a rough visual, it’s roughly 8 pounds for oil tank/Sumpthing and oil.  Weight goes from the triangle to under the engine.  Not a massive shift in weight, but not insignificant either.

George

[dragracer]

You'd be surprised how much difference it makes in moving that weight down low, and forward as far as drag racing is concerned.  Again, ground clearance would be my only concern.

[gschuld]

The Sumpthing will be at the same level as the bottom of the kickstand bracket and be about 1/2” higher up than the bottom of the collector on your V&H sidewinder pipe.

George

[voxonda]

Major set back......primary chains are out of spec. Damn......

[Bert Jan]

Major set back......primary chains are out of spec. Damn......

Ah #$%*.. You know what to do then...

[scottly]

It will be interesting to see how moving the weight of the oil & tank, and putting it under the engine changes the centre of gravity, and if that requires slight suspension setting changes.  Should put slightly more weight on the front end.  Following with interest Rob.

Hey Brian, thanks for your interest. Shifting weight up front and down low will change the C of G just very slightly and I do not expect to have to change my setup. Need to build new pipe because of the low sump, so maybe even have to raise the whole bike a little bit..........

Cheers Rob

If you raise the whole bike a little bit, it will more than offset the shift in C of G from removing the oil tank.