Road Bike V Snowmobile

NZ Racer

New member
Joined
Apr 12, 2009
Messages
4
Age
55
Location
Gisborne NZ
Hi guys from Sunny Gisborne New Zealand ... :-)

Im looking a importing a Snowmobile motor to run in my Dirt Track Sidechair ... See pix

http://brettmead.co.nz/albums/Sport/Speedway/5January_10_2009/Speedway_January_10_2009_056.jpg

Our rules are pretty leaniant and we allowed upto 1060cc. We race on a 400m+ oval dirt track where speed off the line and out of the corners is IMPORTANT. Most unit run Yamaha R1 ... BUT Im looking to push the envolope a little ... ALL my research say that a snowmobile has a better 0 to ?? speed than a road bike.. IS THIS TRUE?? or am I just dreaming...

Snowmoblies seem to deliver more HP and Tougue than Road Bikes ... What Motor would you recomend???

I like the Idea of supercharging a unit too...

THANKS HEAPS

Cheers

Jason

Heres some more pix of us ...

http://brettmead.co.nz/albums/Sport/Speedway/5January_10_2009/Speedway_January_10_2009_009.jpg

http://brettmead.co.nz/albums/Sport/Speedway/6January_17_2009/Speedway_Jan17_2009_072.jpg

http://brettmead.co.nz/albums/Sport/Speedway/6January_17_2009/Speedway_Jan17_2009_075.
 

I can't tell you much on what would be better, but cool pics, never seen anything like that before.
 
Thanks for you help

Thanks for you help so far ...

Heres a NZ site for more sidechair units ...

http://www.sidecar.net.nz/

Been surfin again and found Drag Sleds.. Theses are way cool ... ;-)

Anyone got any good sites for writen off units??

Cheers
Jason
 
I think you will find the 4 strokes to have more power. unless you plan on doing some serious mods to the 2 stroke and want to be rebuilding it. 2 stroke would be lighter though
 
Well, I have no doubt that you could drop a sled motor into a trike like that, I really think it would be easier to drop a bike motor in due to the tranny already built into the motor.

You would have to have some tricky drivetrain to make a sled motor work, but a 2 stroke of similar CC's will weigh a LOT less than a similar sized 4 stroke.

Also, with a 2 stroke you make power every 2 strokes versus with a 4 stroke, 1 power stoke for every 4 strokes. I have a feeling that if you had a 2 stroke and everyone is running 4 strokes of similar displacement, that you won't be allowed to run that 1060c's or anywhere near that.

In reality, sleds can't match the hp to weight ratio of sport bikes, and the drivetrain of a sled has a huge heavy track taking away efficientcy along with all those shafts and clutches. A sled with 120 hp (like my XC600sp) really only makes around 60 hp at the track on a land and sea track dyno. That is a 50% or so drivetrain power loss. Take my sportbike, which is 120 rear wheel hp on an eddy current dyno, and it only loses a few hp, maybe 20. It is reported my bike makes 140 hp at the crank if you take off the std drive train loss on that bike.

My bike is not even close to the fastest 1000cc bike, a newer r1 ( or other 4 cylinder literbike) will smoke it in pretty much every aspect, but as it is does 170 mph, and the quarter mile in the low ten second range at around 140 mph IIRC.

The other issue is that 2 strokes will have a very narrow powerband compared to the wide tq flow of the 4 strokes. That would mean a mis-shift on a 2 stroke if you had a multispeed type gearbox would end up with you getting out of the powerband, and probably getting passed by competitors.

Check your rulebook, or see if a 2 stroke is allowed up to what displacement, and then let us know.

I have a feeling if the people making the rules know anything about motors ( and I bet they do) that a 2 stroke might be allowed, but at a much lower displacement.

Heck, the yamaha nytro 1050 CC 4 stroke is classed against 600cc 2 strokes.

Whatever you end up doing, keep us informed. I love seeing motor powered toys being built.

Tom
 
Done that ....as have others. Using a 2/ is good but 4/ is better.

Calculate the gearing right.

The same load to the secondary is not there..so you have to work with that (no big track or snow to move)

Nothing will get near you..if done right.

Shifting alone - you will gain 6' evertime the competion shifts.
 
Seen it done already!! Bike was dominating the class.. He ran a Yamaha 800cc 2 stroke out of a v-max 4.. Stock carburation and aftermarket pipes.. One of the guys I know that ran that class said they could not run with him in the tight sections of the track where you had to be shifting.. He was always right on the power with the CVT tranny..
Good luck..
 
horkn said:
Well, I have no doubt that you could drop a sled motor into a trike like that, I really think it would be easier to drop a bike motor in due to the tranny already built into the motor.

You would have to have some tricky drivetrain to make a sled motor work, but a 2 stroke of similar CC's will weigh a LOT less than a similar sized 4 stroke.

Also, with a 2 stroke you make power every 2 strokes versus with a 4 stroke, 1 power stoke for every 4 strokes. I have a feeling that if you had a 2 stroke and everyone is running 4 strokes of similar displacement, that you won't be allowed to run that 1060c's or anywhere near that.

In reality, sleds can't match the hp to weight ratio of sport bikes, and the drivetrain of a sled has a huge heavy track taking away efficientcy along with all those shafts and clutches. A sled with 120 hp (like my XC600sp) really only makes around 60 hp at the track on a land and sea track dyno. That is a 50% or so drivetrain power loss. Take my sportbike, which is 120 rear wheel hp on an eddy current dyno, and it only loses a few hp, maybe 20. It is reported my bike makes 140 hp at the crank if you take off the std drive train loss on that bike.

My bike is not even close to the fastest 1000cc bike, a newer r1 ( or other 4 cylinder literbike) will smoke it in pretty much every aspect, but as it is does 170 mph, and the quarter mile in the low ten second range at around 140 mph IIRC.

The other issue is that 2 strokes will have a very narrow powerband compared to the wide tq flow of the 4 strokes. That would mean a mis-shift on a 2 stroke if you had a multispeed type gearbox would end up with you getting out of the powerband, and probably getting passed by competitors.

Check your rulebook, or see if a 2 stroke is allowed up to what displacement, and then let us know.

I have a feeling if the people making the rules know anything about motors ( and I bet they do) that a 2 stroke might be allowed, but at a much lower displacement.

Heck, the yamaha nytro 1050 CC 4 stroke is classed against 600cc 2 strokes.

Whatever you end up doing, keep us informed. I love seeing motor powered toys being built.

Tom

Very well said. and just as a fun thing for me, I know and am friends with the guy that started and runs/owns Land and sea. they make a REAL nice product!
 
Thanks Heaps

THANKS HEAPS for ALL your comments... Its bloody hard to get an insite on Snowmobiles and there potential when there only prob a doz or so in the whole country.. haha

Heres our rules re Motors ...

http://www.speedway.co.nz/pdf/Rulebook/G - Regulations.pdf

T9-2-6 Engine:
(a) The cubic capacity of the machine is limited to 1,000cc
plus 60cc tolerance and only the rear wheel of the
machine shall be driven.
(b) Owners of vehicle must make individual arrangements
with track steward or qualified Speedway New Zealand
Official to inspect, certify and seal each individual
motor before vehicle can be raced. NO SEAL, NO
RACE.
(c) On liquid cooled engines an overflow pipe must be
used which directs any overflow of coolant away from
the rider and passenger.
(d) Engines shall be covered by a fuel tank or guard to
ensure the engine cannot be contacted by the rider's
body.
(e) Electronic Fuel Injection systems are permitted.
(f) Any engine inspected and found to contravene the
rules will be declared an illegal engine.


So either 2 or 4 stroke doesnt matter.. Turbo/Superchargers still doent matter. Nothin bout Drive chain config either .. There are some construction rules.. But they mainly refer to "THE OVERALL LOOK OF A MOTORBIKE".

Most guys are running R1 or GSXR's

I want the power off the line or out of the corners... We only run on a 400+m banked dirt oval track...

Ive rung a dealer in the states the other day ... Very helpful he was too ... He suggested that a MACH Z or A Tripple would produce upto 200hp standard.. BUT Id like to stay with a RX1 or simular as they are base on the R1 and most motor parts should cross over???

Thanks guys for ALL your input... Any good selvage sites or 2nd dealers that would rip me off being on the other side of the world...
 
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the rx1 motor pretty much IS an r1 motor. I would stick with the bike motor and skip the hassle of clutching a sled motor
 
03viperguy said:
the rx1 motor pretty much IS an r1 motor. I would stick with the bike motor and skip the hassle of clutching a sled motor


The Rx1 motor is based off the first generation R1 motor. I would stick to the bike motor as well.

I am amazed that the rules don't say anything about 2 or 4 stroke or power adders, even nitrous.



I would take a 4 cylinder r1 or similar bike motor and throw nitrous on it fort he last straight. See how long they allow that.
 
Quick question ...

With the CVT wont that help prevent wheel spin ...

All that Ive read seems to point to the CVT being the diffence in OFF THE LINE speed .. True / False

Cheers
JASON
 
03viperguy said:
I would think only that it might slip more than the regular gearbox


I would think so too.

I mean you could do it. I have a Polaris sportsman 500HO ATV, and it has CVT clutches. It is very smooth and works pretty well as long as the belt stays dry.

Which would also tell me that if you go CVT with a sled motor, that you would have to really shroud the clutches from mud/ water.
 
Last edited:
horkn said:
I would think so too.

I mean you could do it. I have a Polaris sportsman 500HO ATV, and it has CVT clutches. It is very smooth and works pretty well as long as the belt stays dry.

Which would also tell me that if you go CVT with a sled motor, that you would have to really shroud the clutches from mud/ water.
we should hang out, move back east would ya :) we seem to agree on a decent amount of things lol!
 
03viperguy said:
we should hang out, move back east would ya :) we seem to agree on a decent amount of things lol!

Eric,

I am trying to plan a trip with my GF and bike out to NH and Maine once things calm down and turn around. Maybe in fall, just before or after prime leaf peeper season. My Gf has only seen Boston on a business trip, so I told her I need to show her the "real New England".

When we get to that point, I will pm ya.. Maybe we can meet up:)


Tom
 


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