Hey Ray, good to see you over here!! Guys this is the man you all want to be talking to when it comes to big HP for the V's. Maybe he even knows some tricks for the Rotax engines..... Hmmmmm

Ken

 

Well I just snapped my crank today Ken, Maybe its time to send this motor off. Anyone want to do a little sponsorship for a already fast motor.... [img]i/expressions/face-icon-small-smile.gif[/img] Hows the canadian shippng exchange?

 

NO WAY!! Big bummer!! How did that happen? I guess that is the price we pay cranking small v-8 power from these little engines, huh? Still that sucks bad and I feel terrible for you man. I love to go fast but I hate to pump out cash for repairs.....

I know the exchange rate is pretty good now and shipping isnt bad since we save on the exchange rate. Mine was about 400.00 round trip to Nova Scotia, which is way on the east coast of Canada. Wish Ray would move his operation to Las Vegas.. Hint Hint Ray!!

So what is in the works now??

 

Not speaking for Ray by any means, but I had an email conversation the other day with him. I was inquiring about DS stuff and he responded by saying that he has done a little work with the monster rotax but not enough. He suggested going to established guys like RWR. Obviously he may not be familiar with HPR and others or I'm sure he would have mentioned them.

Mario, I've tried to call a couple of times...... after you dropped that bomb on the phone, I've been thinking about it ever since. SUCKS!

Alright fellow DS Brothers what do we have in the parts bin for Mario to get cookin' with fire again???

I know that he's got some parts but I don't think stock will do. Anyone have a crank laying around? I believe he has a jug....

 

I hate to hear about Mario's motor. If Biggerisbetter still has his stage 2 1/2 DS650 motor for sale thats where I would start. It has a strong base with back cut tranny lower end & all. If you don't need the top end than it could be sold to get some of the money back. That motor was a strong runner. Thats a option to start with if it's still available.

 

good call countryjoe.....

Bigger, where are you?????

Help!!!!!!

Talked to Mario, and he's looking into the Bigger motor.

One questions though. What is a back cut tranny???? [img]i/expressions/face-icon-small-confused.gif[/img]

 

My bad, I think that the tranny had the gears back cut for better shifting?

 

Now we're making sense..... sorry, I aint had much learnin'

 

Guys, sorry to burst your bubble, but 100HP @ 7500 RPM on 12:1 compression pistons are not possible. I run some math on this and the Volumetric efficiency shows off the charts on this motor. I run the figures with an 800cc making 100HP at 7500 RPM and it showed me this motor has a VE of 123%. 123% means this motor is consuming 800cc plus 23%, meaning it breathes the same amount of air as a 985cc motor filling 100% of it's capacity. Without a turbo or Nos to boost normal aspiration, it is IMPOSSIBLE for this motor to make 100HP at 7500 RPM. Now if this motor is a 730cc it means it has a VE of 135%, meaning the 730cc is breathing the air of a 985cc motor. Clearly that is not possible.

Just to put these claims into perspective. A Formula 1 car does not have a VE of 123%, nor does a superbike or any other normally aspirated motor. A 750cc superbike with a pipe and a well tuned motor does not make 100HP at 7500 RPM. It only makes around 70HP.

For a 800cc to make 100HP you need to crank it up to 10 000 RPM and have a perfect filling cylinder. More likely, you need to crank if to 11 000 plus, since it is nearly impossible to fill a cylinder to 100% of it's capacity at very high RPM. Looking at a 750cc superbike motor and you also get 100 HP at around 10 000 RPM and these motors are built for it and sues much smaller pistons and higher compression.

The problem with the KFX is the belt drive. It messes with the figures on a dyno and reads way higher than what it should. For example. I have seen dyno runs on a KFX700 where the dyno shows around 65HP, and the bike only had a new pipe and jet kit on it. The rest was stock standard. Kawasaki themselves claim 49HP at the crank with this motor, so how does a dyno show 65HP with just a pipe and jet kit? Keep in mind this 65HP run was also done with the stock tyres. If it had dyno tyres on, the HP output should have been closer to 70HP and this was figures at the rear wheels.

Dynos are made to run at a fixed gear ratio, something that you cannot do on a KFX, since the CVT changes constantly. The only way to get accurate HP figures on a dyno is to the lock the CVT in one position and then run the bike. If you don’t you just messing the dyno number up big time.

If I work it out mathematically, a well tuned KFX 700 (730cc with 12:1 compression) should provide around 65 to 75 HP at the crank if it has a VE of around 90 to 110 %. 65HP plus should make for a very quick bike, especially with a CVT keeping the gear ratio and power output perfect all the way. There is no argument, that it will be quick and eat up most other quads.

But 100HP is impossible without NOS or a turbo.

 

any big hp numbers ARE POSSIBLE with the right dyno[img]i/expressions/face-icon-small-wink.gif[/img] seems there are a few "loose" dynos around..... things sell better that way