CBR F4 RPM range? [Archive]

Dominic Venieri

12-05-2002, 08:41 AM

To the teams out there using the Honda CBR 600 F4/F4i:

We've just switched to this motor, and were wondering if anyone could share information as to what RPM ranges you are running at. Mainly, how high up do you go. We've heard from F4i owners that they've taken the bike just over 17,000 rpm. Stock redline is at 14,500, and our TEC-3 can support 20,000 RPM. We're curious as to what range some other teams are tuning to, to set ourselves in the right ballpark.

Also, if anyone has the gear ratios for the F4i, we'd appreciate that, since the factory service manual doesn't include them.

www.formularpi.com (http://www.formularpi.com)

spunkb0x

12-05-2002, 12:01 PM

The factory service manual does have the gear ratios.

gtmsracer

12-05-2002, 01:31 PM

I wouldn't rev the F4i motor too far past the stock redline. I think Honda knows their stuff when it comes to picking a redline. Plus, with the 20mm restrictor, you can't make enough power to make it worthwhile to rev that high anyways. We rev to the stock redline.

Shamus Yandle
Georgia Tech Motorsports 1998-Present
2001/2002 Formula Student Champions
2002 Formula SAE - 3rd place

David Money

12-05-2002, 02:51 PM

We recently did a small test on a track that was set up to be representative of the FSAE course and our star driver was typically staying in the 7000-11000 range on our F4i.

Spike

12-05-2002, 10:30 PM

Well the owners that told you that they rev to 17,000 rpm is smoking to much rock. The f4/f4i stops making power at 12,800 with stock cams and 13,500 with the HRC cams. The HRC ECU doesn't raise the rev limiter so that tells me that it wouldn't make much sense to rev past the stock limiter. And I really don't think that HRC was to worried about durability because if you can afford the engine powerup kit (5500US) you can afford the rebuild the motor every three races.

Dominic Venieri

12-06-2002, 07:51 AM

Thanks for the replies guys. We'll get it sorted from there.

www.formularpi.com (http://www.formularpi.com)

MikeWaggoner at UW

12-08-2002, 12:48 PM

Since you're sucking through a restrictor, you tend to get MUCH poorer volumetric efficiency around .7 mach through the restrictor... It's easy to calculate this by using engine volume etc. but you'll find the stock RPM limit is more than adequate...

Western Washington University FSAE
dot.etec.wwu.edu/fsae