Chasing speed on sand....


#1
Hi all.
I'm looking for a bit of advice for next year's attempt to extend my record at Pendine.
My bike has a yoshi system, power commander 3, and is the first gen1 so no top speed restrictions.
I hit 169mph on the sand, at the mile, and know there's more there. Biggest issue is wheelspin.
One of my intentions is to lengthen the gearing, ie lowering my torque levels to help, and maybe giving me a bit more reach if the conditions allow a longer run. Any ideas of recommendations as I believe I'm running standard gearing at the moment, but will confirm that later.
Also tires. I was using my standard road tyres that were on the bike when I got it... Pirelli angels, which if I'm honest spin up on the tarmac never mind sand, so should I go the Michelin pr5 route? And its a 200 rear, should I drop back to 190, even 180 for a smaller footprint, like the salt for more speed?
And obviously power. I'm in the modified 1350 group, non turbo, and have a bit to spend engine wise. The exhaust cam swap? Is that a drop in solution or do some adaptations need to be made.
Also, I've committed to loosing some weight, so I must be serious.... Haha
Any ideas input gladly welcome. And thanks in advance.
 
#2
I don't know that any tire short of a paddle isn't going to spin on sand, so I'd think gearing to minimize it is the way to go. If you're staying all motor, cams exhaust and a tune is good value for money. Everything else is an exchange. A sidewinder will give you great power at the expense of streetabilty, but there are other options. Lighter oil frees up power, at the cost of lubrication, etc.
 
#3
I do not know squat about sand speed. However. From drag racing I can tell you I pump up my front tire about standard to minimize the foot print. Nothing stupid. I run 45 psi cold. Sand may be a very different animal
I would think lowering the bike would help reduce resistance
A double bubble windshield may actually help as it should give you someplace smoother to tuck in behind
Good luck
Jp
 

VIPER

Formerly known as viperblackbusa.
Registered
#6
I would look into a shinko rear 200. I would also look at plus 1 tooth on the front maybe minus 1 or 2 on rear. This will keep spinning down some. I think i would dump the power commander. switch to the newer charge system and the newer ecu and invest time learing ecu editor. You didnt mention a stretch...might not hurt to look into that some as well.
 
#7
Sidewinder is a type of exhaust, primarily used in drag racing. very little backpressure, designed to maximize exhaust flow at high rpm.

tsukigi.jpg
 
#8
Low is good, less rolling resistance is good (but comes at the expense of traction), longer is usually more stable. Is this a bike you ride on the street?
 
#9
once a bike is lowered for racing purposes there is no room underneath the bike for the exhust pipe A side winder goes out to the side Usually the right side and flows along the bike mere inches off the ground . It is a good pipe for competition but makes turning to the side its on a bit of an adventure
shown here on a busa . Note the part about trimming the fairing
ssb-voodoo-sidewinder-16.jpg

Once all the pieces are aligned you can snug down the bolts starting at the headers and then working back. Be sure to check your clearances, too. The final step is reinstalling the fairings once you've trimmed them to fit the new collector pipe and muffler. Unfortunately our bike was a loaner and we had to run the system without fairings.
Photo: SSB

more pictures of the in stall on a busa here .
https://www.superstreetbike.com/tech-voodoo-moto-sidewinder-exhaust-install
 

sixpack577

Top Gun
Registered
#12
FYI
Only 99 and 2000 model Busas are not speed limited. 01 and newer, every Japanese sportbike is, to 186mph/300kmph.
02-07 are the only gen1 Busa's that can have their ecu's flashed. 99-01 can be converted to 02-07 parts to make it possible to flash them.
I also have no idea about land speed racing on sand. I'm curious if a more dirtbike style tire would help or hurt things.
Just get studded ice tires and try again in winter, lol
Good luck, and looking forward to your results.
 
#13
Thanks for all the replies! Yes the bike is still a street bike and I often commute on it so right now, a stretch and sidewinder wouldn't really suit as our roads are very twisty!
The bike is registered as a 2002 but it was sitting in the dealers for a long time, and I'm have sent the ecu to schnitzel racing and they got back to me confirming its a 99 ecu so they are unable to flash it. So. In one way that's good, no 186 limiter, but maybe a update ecu will give me more options...
The gearing option is a definite way forward. All exciting anyway!!!
 
#14
A newer ecu will give you the ability to use ECU editor, which is cheap and good. Weigh that against the cost of getting a dyno tune with what you have now. Find the exhaust which gives you the best power, Yosh's are not known to be the best on our bikes. Another thing I forgot to mention earlier is the head. Good headwork will clean up the casting choke points, when combined with cams and a tune, you will have an appreciable increase in power.
 

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