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Computrainer help?(5 posts)

Computrainer help?DougSloan
Aug 26, 2002 9:29 AM
I got the CT (3d Pro) up and running. It seems that no matter what I do, my indicated speed at a certain HR (output) is much lower on the CT than it would be on the road. Is this normal?

I did the coast down calibration. It came out to 3.91 several times. I did save it.

I set the roller tension as light as I could while avoiding tire slip.

I set my weight to include the bike weight.

I still find that an output that would normally yield about 20 mph on a level road gives me only about 15 mph on the CT. I'd like the CT to mimic "real world" riding as much as possible, though, but with repeatable results, too. Assuming I'm not doing something wrong, is there a way you could "fool" the CT into indicating speed more closely related to road conditions? Thanks.

Ps. Any further tips on using the CT?

calibration seems hightao
Aug 26, 2002 4:04 PM
Not sure what version you're using but anytime my calibration is over 2.00 the resistance seems more and more unrealistic (harder) the further up the number is. Likewise, under 2.00 and it seems too easy. Not to say you have to do exactly 2.00 but within 10 to 20% really seems to help. Make sure your rear tire is at max pressure and very clean, this should help you get better traction at 2.00. If this doesn't work you may need to mount the trainer to something like a piece of heavy plywood.
re: Computrainer help?wisill
Aug 29, 2002 7:46 PM
Doug, I got a computrainer this year and noticed the same thing in that the speed on the computrainer is about (for me) 1 to 1.2 mph slower than what the cyclecomputer reads. This is because the comutrainer speed is not based upon the wheel circumference but torque. Just ignore this difference.

Did you say 3.91 for calibration? Immediately loosen your tension and get it somewhere around 2.00. I ride at 2.1. Your 3.91 calibration is creating excessive tension and heat in the flywheel-you will blow! this in the near future. Replacement cost could be $400.00. Make sure you have a small fan blowing air into the flywheel to ensure it doesn't overheat.
thanks; it's better nowDougSloan
Aug 30, 2002 5:53 AM
I cleaned the tire with alcohol, as suggested, pumped the tire up to 130 psi, and backed of the tension as much as I could while avoiding slipping. Also, I built a platform similar to what's described in the CT info packet. That dropped the calibration down to 2.1, and the speed is much closer to real conditions. Now, it's much more enjoyable.

If they would only build in a motor, too, to simulate descents, you'd hardly know you were not on the road.

I really like this thing. The best part is racing against a stored performance.


thanks; it's better nowwisill
Aug 30, 2002 1:58 PM
Remember, you can ride without "racing" against previous performances or the pacer. You can also ride against someone on-line. You may need to frequently (every time?) clean the tires with the rubbing alcohol to ensure correct calibration.