Board logo

R1 BEC on the Rolling Road
hogman - 16/9/08 at 08:14 PM

For all you guys running R1's in your BEC, has anyone had their car on a rolling road, if so here are a few questions for you....

1. What year/model R1 engine was it?
2. What was you maximum BHP/torque at the wheels?
3.What was you maximum BHP/torque at the crank?
4. Any mods to the engine?

Hope we can all collate the info and have some form of reference. Once my 4xv is rebuilt I will be RR it and will post mine.

Cheers
Kevin

hogman - 16/9/08 at 08:49 PM

Hi Chris

Thanks for the reply, I know the variables are vast when it comes to RR figures, just thought it might have been interesting!

Very surprised to read you found there was more power output when using the standard airbox over the sausage filter! Would have thought it would have been the other way around! Any ideas as to why?

Cheers
Kevin

McLannahan - 16/9/08 at 09:03 PM

Sorry to hijack but is it worth then converting to a home made airbox over a sausage filter? I have sausage but like Hog didn't think it would make THAT much of a difference!!

smart51 - 16/9/08 at 09:10 PM

My engine is a 1998 4XV. It made 152 BHP at 10150 RPM and 108 Nm between 9000 and 9600 RPM.

That was with an airbox made by myself. Me experiments show the R1 airbox to be more restrictive than mine but then their exhaust is more restrictive too. I also had my own carb trumpets fitted that I had turned out of aluminium. For reference, I have 150 main jets since the dyno session.

smart51 - 16/9/08 at 09:15 PM

quote:
Originally posted by chris mason
yep, yamaha no doubt spent millions on r+d for there airbox design, whereas pipercross etc, just got a bit a foam and called it a filter.

if a sausage filter was better then yamaha would have fitted them as standard

Chris


Well, tens of thousands perhaps. Their airbox will be the best it can be and fit under the fuel tank, which in turn has to fit under the rider's chest.

You should bare in mind that their design contstrains also include noise suppression and filling in the nasty torque flat spot that they have. In terms of airflow, it doesn't have to be the best possible, it just has to restrict flow less than their exhaust.

Fit a straight through can and the next restriction is the airbox. With more room to play will and less restriction on drive by noise, you can make yours flow more air than Yamaha's. You don't have to worry about mass production costs too.

trottski - 16/9/08 at 09:42 PM

quote:
Originally posted by smart51
My engine is a 1998 4XV. It made 152 BHP at 10150 RPM and 108 Nm between 9000 and 9600 RPM.

That was with an airbox made by myself. Me experiments show the R1 airbox to be more restrictive than mine but then their exhaust is more restrictive too. I also had my own carb trumpets fitted that I had turned out of aluminium. For reference, I have 150 main jets since the dyno session.


Is that at the wheels or the fly? I'd guess the latter.

Also, would you be will to make another air box and trumpets for a reasonable fee?

Paul TigerB6 - 17/9/08 at 12:08 AM

I've heard of up to 170bhp from a carbed R1 and to be honest wouldnt be too surprised to see 152bhp at the wheels on anyones car (given the discrepancy you might see).

I'd still go on driveabilty over paper figures though!!

smart51 - 17/9/08 at 07:18 AM

quote:
Originally posted by trottski
quote:
Originally posted by smart51
My engine is a 1998 4XV. It made 152 BHP at 10150 RPM and 108 Nm between 9000 and 9600 RPM.

That was with an airbox made by myself. Me experiments show the R1 airbox to be more restrictive than mine but then their exhaust is more restrictive too. I also had my own carb trumpets fitted that I had turned out of aluminium. For reference, I have 150 main jets since the dyno session.


Is that at the wheels or the fly? I'd guess the latter.

Also, would you be will to make another air box and trumpets for a reasonable fee?


I said to the rolling road man "152 BHP, thats great. What is it at the flywheel?" He looked quite sheepish and mumbled. I didn't push him any further. The car felt faster than before the dyno session so it was worth it for me.

As for making airboxes, I'm struggling to find time to make my new car before IVA, sorry.