Sandrail Hayabusa CLUTCHLESS downshifting at WOT

uaeproz

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I have a buggy (sandrail with paddle tires – and please note paddle tires makes heavy load on the engine/transmission in addition to the total weight of the sandrail) with Gen 1 Hayabusa Engine on it. Here’ are the specs of the engine:
• Upgraded gears, Back cut transmission, heat treat,30mm counter shaft
• Lock-up clutch
• Power commander 3 usb
• comp Turbo (being installed)
• 44mmV-band Tial Wastegate (being installed)
• 50mm Tial Blowoff Valve (being installed)
• In-line Fuel Pump (being installed)
• Fuel Pressure Regulator (being installed)
• Airbox/secondary injectors / Billet Aluminum Airbox/Intercooler and Secondary Injectors (being installed)
• Electric Waterpump + custom heat exchanger (being installed)
• Fuel Controller with 40psi Internal Map Sensor (being installed)
• Oil Blockoff Plates
• Crankcase Vent Filter
• High Flow Airfilter (being installed)
• Carrillo H Beam Rods (being installed)
• Wossner turbo pistons (being installed)
• Spacer Plate (being installed)
• Adjustable cam sprockets (being installed)
• ARP cylinder studs (being installed)
• Microtech data logger (with laptop adapter)
• HD valve springs (being installed)

I'm looking for clutchless system. WOT UPSHIFTING And WOT DOWNSHIFTING.

I have concerns on reliability considering the heavy loads on the engine/transmission.


I’ve been arguing with my friends about going forward with CLUTCHLESS SHIFTING. I will try to explain the sand load situation in here as much as I could so that you can imagine and understand the argument:
The sand here makes the movement of vehicles very tough even on flat surface, Imagine that you have a turbo haybusa engine installed on a full size car with full slicks rear tires and pressing about 20 to 25% or brake all the time (sand vs asphalt). This is almost a resemblance of the load I’m talking about on the engine and drive train.

The differential that we have on the sandrail is linked to the drive sprocket through a motorcycle chain not through a coupler or shaft or gears like quaife differentials. So, main bottleneck here is the chain.

Examples, when we release the clutch suddenly at WOT at first gear while the sandrail is at full stop, probably 2-3 times of doing that will break the chain. If we were upshifting at WOT and releasing the clutch suddenly while the sandrail at mid speed, probably 5-6 times will break the chain.

If the clutch is fully engaged, then we have absolutely no problem with the chain at all.

So, the use of clutch particularly sudden clutch release is a bad thing to do. My argument with my friends is that, using clutchless system upshifting/downshifting is the way to go and that will enable us to avoid using clutch.

However, during the uphill drive, the load is doubled cause the dunes here are huge (about 100 meters) and so steep (have a look at this dune: https://en.wikipedia.org/wiki/Moreeb_Dune) and in some cases we can’t make it over the top simply because when we downshift, we lose time/speed cause we can’t downshift at WOT.

I hope this explains the full picture.

Does anyone know of a system that allow UPSHIFTING AND DOWNSHIFTING at WOT that is safe and reliable and will not harm the transmission?

Thanks,

Abdulla
 
Quick shifters from dyno jet , and others work by killing ignition or fuel for milliseconds . They use a type of pressure / or strain gauge to detect the movement of the shift arm and kill a predetermined amount of time usually 50 to 75 milliseconds per shift and its adjustable . A push button system is the same but kills the motor on the up shift ( drag racing application ) when the button is depressed . They dont down shift on air systems . Electric models can sometimes do both depending on make/model . Do you have a picture of the cart/shift arm assembly being used ? Quick shifter is the best choice for up/down shifts , but not sure
still about WOT down shifts . A blip of the throttle is used generally in down shifting .

Maybe a better over all gearing selection is required so a down shift wont be required .
 
Quick shifters from dyno jet , and others work by killing ignition or fuel for milliseconds . They use a type of pressure / or strain gauge to detect the movement of the shift arm and kill a predetermined amount of time usually 50 to 75 milliseconds per shift and its adjustable . A push button system is the same but kills the motor on the up shift ( drag racing application ) when the button is depressed . They dont down shift on air systems . Electric models can sometimes do both depending on make/model . Do you have a picture of the cart/shift arm assembly being used ? Quick shifter is the best choice for up/down shifts , but not sure
still about WOT down shifts . A blip of the throttle is used generally in down shifting .

Maybe a better over all gearing selection is required so a down shift wont be required .

I've checked all over the places but unfortunately I couldn't find a system that allows downshifting at WOT. A blip won't work at WOT.

I've got in touch with Graham from Flatshifter. He's very friendly and gave me clear responses. The blip they have won't work at WOT but they are developing something that will allow that but it's gonna take at least 2 months

We tried gearing, unfortunately in the dunes, you get surprises where you have to downshift or get stuck.
 
I know this is probably not what you want to hear and a little off topic BUT it seems
that this would be a job for electric motors. NO SHIFTING.
Not sure if you could use the motor to drive a generator so no batteries were needed.
No chain either with motors at the wheels. Instant power too.

But all that cost $$$$ and a lot of work to change over to it.

Sorry but that thought just came to me and thought it would solve your problem.


WOT upshifts are not a problem like the downshifting part.

Good luck in your search for a solution to your problem.

Sorry I couldn't help more. :banghead:
 
IMO you are looking for a unicorn using the standard gearbox. Currently you need some fairly advanced electronics and gearbox innards to be able to even auto-blip the throttle on downshifts. BMW, Ducati and Yamaha have it on their high end superbikes and the MotoGP guys have "$eamless" gearboxes.
If you want to get creative dry sump it, cut the gearbox off and figure a way to put a CVT out of a car or a big bad ass snowmobile on it.
As expensive as that sounds it may be cheaper than trying to get a stock gearbox and after market electronics to function as you wish.
This is my opinion your results may vary.
 
I hear that you desire to extend the service life of the chain without compromising the 'fun factor'.
I experienced a similar issue several years ago after I installed the busa in a 1400# car for daily driving. The chain would turn blue and fail frequently after high speed driving or after lifting the front end (mid-engine) at take-off (fun, but expensive). Also, the differential had to pivot to allow for frequent chain tightening.

My solution was to remove the chain and install a Ragemotorsport in-line drive unit bathed in sysnthetic oil. Simple install. The front end couples the output shaft of the tranny and the aft end inserts into the Quaife. Launching or just everyday driving now is so predictable. Wear? or Failure? I purge the fluids every ~5k miles and all is fine. I change the clutch rings early at ~10k. Recently, I replaced the inner and outer basket/sleeve due to excessive 'notching'. The WOT shifting with the PC quick shift is between #2 thru #6 upshift only. Suggest you replace your 1st gear with a higher ratio. I did, along with a 2mm crank and my acceleration from 0 is so much smoother, quicker engagement and less wear on the clutch. The 2003 motor had 40 miles when installed and now after 7 years has ~35k.
 

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I hear that you desire to extend the service life of the chain without compromising the 'fun factor'.
I experienced a similar issue several years ago after I installed the busa in a 1400# car for daily driving. The chain would turn blue and fail frequently after high speed driving or after lifting the front end (mid-engine) at take-off (fun, but expensive). Also, the differential had to pivot to allow for frequent chain tightening.

My solution was to remove the chain and install a Ragemotorsport in-line drive unit bathed in sysnthetic oil. Simple install. The front end couples the output shaft of the tranny and the aft end inserts into the Quaife. Launching or just everyday driving now is so predictable. Wear? or Failure? I purge the fluids every ~5k miles and all is fine. I change the clutch rings early at ~10k. Recently, I replaced the inner and outer basket/sleeve due to excessive 'notching'. The WOT shifting with the PC quick shift is between #2 thru #6 upshift only. Suggest you replace your 1st gear with a higher ratio. I did, along with a 2mm crank and my acceleration from 0 is so much smoother, quicker engagement and less wear on the clutch. The 2003 motor had 40 miles when installed and now after 7 years has ~35k.

Thanks for your reply. I'm not sure this will fit. Can you share more pictures from the top/side showing the head and the drive shaft location. It will give me better view.
 
I will have several pics in a few days as I will be removing the assys from the car. A noise has developed. Maybe a bearing or...
 
First pic is a 'stock' pic.
Second pic shows contents. Disregard the reference to the 'waterpump' and 'existing part'. Although item 31 slides on the transmission output shaft in lieu of the sprocket.
Third pic is with the unit installed. The car muffler was only temporary before the two-brothers cans
Forth pic is with the unit removed.

Honda transfer mounting.jpg


20140518_094022.jpg


20151020_181604.jpg
 

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  • Ragemotorsport unit.pdf
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