Donor Gearboxes

[husaberg]

Maybe I need to take a trip to pick a part, I wonder how big that Mazda one is. It looks like something that would work.

If I run an R6/GSXR/similar pump off the clutch cover, I could run it faster At 80-100% engine speed. I do like the idea of a belt driven standalone unit though, for servicing and ease of integrating into the design. It could just bolt under the engine on a plate and either be driven from the end of the crank or layshaft depending on which way I need it to spin. The other benefit of belts is they can raise or lower the pump speed fairly easily.

looks like you need a puller

here is the size, its a big en but if you want flow....

It says to avoid the partial plastic one.
https://www.aliexpress.com/item/1005004102032453.html
https://www.aliexpress.com/item/4000987054104.html

[el chupacabra]

I don’t think I’ll be happy with anything available to be honest. Looks like I might have to make a something a bit custom. Maybe use the SV 1000 internals and have a dual outlet pump on the clutch cover or maybe just 1:1 off the end of the layshaft or tucked away under the motor running from a belt.

Does anyone have anything suitable kicking around? I’m more than happy to pay for it, or look around on trademe.

I should’ve just made it air cooled using TF125 cylinders haha.

[F5 Dave]

As long as you were happy with about 48hp and an extra 4" girth for the fins.

[husaberg]

https://www.trademe.co.nz/a/motors/m...ing/4188418953
golly its huge vicar.

[el chupacabra]

OK, TF125 jokes aside. I think I've sorted it, here is a bracket holding 2x 6200 sealed bearings, I can bolt this to the motor anywhere holding the R6 water pump I've asked the wreckers about. I can either drive it from any of the cranks or the Lay shaft. I can decide on the exact pulley specification once the pump is in my hands and I can measure it and model it accurately. The pump will bolt to the back side of this and have its bearing replaced with a sealed one also.



It could even be like this and I could hand pack the bearing with grease.

[husaberg]

This the open flow specs of a 09 CBR600RR

Count the teeth to see the reduction

This is a R1 pre 07
The resuts:
5-6000 RPM - 20.65 litres per minute. (5.455 us gallons)
8000 RPM - 34.43 litres per minute. (9.095 us gallons)
10000 RPM – 55.720 litres per minute. (14.72 us gallons)

[el chupacabra]

It looks to run at about 52% crank rpm give or take for the R1, I’m sure if you spin it too fast It could lead to cavitation in the pump or maybe it won’t, unsure but I could shoot for around 75%

[husaberg]

Flettner makes his own water pumps.

But he does make is own practically everything

[el chupacabra]

I wonder if he’s super concerned with flow. I’m sure 30L/min would be fine but it would leave HP on the table, how much is anyone’s guess. If the R6 pump is cheap enough I’ll just go ahead with that and change plans later if it is unsatisfactory. I’m not ruling out making my own pump but I want to avoid making anything I can, it’s either lazy or smart depending on how you look at it.

[el chupacabra]

$150 for a second hand R6 pump, scratch that. I’ll compromise and make half of a pump, I’ll make an inlet for a gsxr1000 pump, and If I’m not happy, I could probably make a new shaft as the impeller is removable if I still belt drive it or I might drive it from the Layshaft.


Part is ordered so I’ll start making more progress once it eventually arrives.

[el chupacabra]

Otherwise, I assembled the clutch onto the input shaft today and found out there is indeed a sprocket on the rear of the clutch to drive the water pump that I am missing. I managed to contact the guy I bought the gearbox from and he is sending it to me. I may have designed the oil/water pump combo differently had I had this part at the start. Once everything was together I saw how far the clutch actually sticks out past the cassette so I needed to move the NJ roller bearing for the lay shaft out 16.6mm further so as not to create a weak point where the shaft would deflect. This makes the cassette look fairly wide at 46mm from one side to the other not including the protrusion for the shift forks.

This means after that panic where I translated the whole cassette to the right, I can probably shift it back around 10mm to make the engine slightly narrower or maybe I don't bother with only 10mm at stake.

[el chupacabra]

Progress has been slow whilst waiting on parts. Today I have sorted out the oil feed to the output shaft, it is a 3 piece solution with the output shaft feed doubling as a bearing retainer. Drilling a hole through the case for an oil gallery just seemed like too much faff with such a long hole in order. All three of these parts can be made from 6082 on my small CNC mill and manual lathe.

[el chupacabra]

The Chinese crank showed up today. I’m wondering whether to run the inside bearings with premix lubrication or lubrication from the gearbox oil. All it’ll mean is switching sides for the oil seal. I’ll need to make up some collars for the bearing to run on, I think 4140 should be ok as SKF say a minimum of 35 HRC is needed for rubber seals.

Any thoughts or preferences on the matter? As to which side to run the bearing.

[husaberg]

The Chinese crank showed up today. I’m wondering whether to run the inside bearings with premix lubrication or lubrication from the gearbox oil. All it’ll mean is switching sides for the oil seal. I’ll need to make up some collars for the bearing to run on, I think 4140 should be ok as SKF say a minimum of 35 HRC is needed for rubber seals.

Any thoughts or preferences on the matter? As to which side to run the bearing.

IMO on older small 2ts the bearing on the mag always tends to let go first. This is the one that is only petrol/oil lubed. I don't believe this is a coincidence.

[jato]

moving the main bearing 8mm to allow an inboard seal could see the crank flex 20% or so more at max revs depending on the rest of the crank's design. If lube of the bearing was going to be scant on the bottom cylinders it may give better reliability to move the bearing... it might be worth doing a sketch of the proposed crank layout and and then look at the loads and distances involved. i would guess that there would be something like 4000n of force on the crankpin at full revs. if you wanted to get an accurate figure we'd need to get some weights of reciprocating mass.