Trainer Resistance Question

I would be leery to posit a solid correlation between trainer bike speeds, HR, and the resistance on those units. There's too many ways for the results to be wonky from ride to ride. If you're in your targeted HR zones, that's good.

Just remember that your performance is not a linear curve...it has ups and downs even throughout your training season, based on your specific training, what you've eaten, how well you've slept, what the temperature is, how hydrated you are, etc.

I just realized that I did nothing to answer your question. My apologies.

When you say "I set the resistance and have just left it" are you refering to the force with which the resistance unit pressen on the tire's rubber? The way I understand it you should tighten it to just where it touches the rubber and then give it one more turn. If you find that the tire is slipping on the metal roller give it a little bit more. Too much force will wear down your rubber unnecessarly fast.

My 'resistance' adjustment comes from the bike's gears and the non-newtonian resistance fluid which increases in a resistance as speed goes up.

 

First successful trainer experiences have been in the last two weeks.  Prior to that, my trainer was hideously hard and I smelled rubber burning (seriously).  Took it to people to check it and they said it was fine.  Still problems , took it again, they said it was defective and got a replacement (Cyclops)....all that to say I am NO EXPERT, but I think absolutely everything on the trainer is questionable as far as it's accuracy and relevance to outside "real" riding (except maybe watts, but I know nothing about power meters).

I make contact between the fly wheel and my tire, then tighten 1/4 turn.  From there, I shift to make more or less difficult and can get hy heart rate anywhere I want it based on my shifting and cadence.

I know that outside, I average 17 MPH, so I use only my time on the trainer and figure my mileage at 16 MPH.  Just what I do.

I got a KK road machine too.  I turn the knob until the metal touches the tire, then tighten 2.5 turns.  I average about 15-16mph on the trainer on my long rides.  Outside Im around 18-19 mph on the same RPE.  there's too many variables.  I just dont worry about the "actual" speed on my display. 

I have heard bascially the same as what others have said.  Put the resistance setting so the trainer wheel just touches the bike tire then give it another good turn.  No more.  If the tire is slipping a little when spinning then it's too loose, if it's got pressure on it, it's too tight (and will wear out sooner as others have said).

My road speed is usually about 1.5 mph lower than my trainer speed, and I attribute that primarily to wind resistance when riding outside.

Put your bike on the trainer and tighten the friction until the wheel's touching the wheel

Grab your wheel and pull up as hard as you can.
If it squeeks, tighten the friction 1/2 turn.
Repeat until it doesn't squeek.

After that get on your bike and put it on small front chain ring and about 3 or 4 down from your largest cog on the rear.

Bring one pedal up to the 12:00 position and honk down on it as hard as you can.
If it squeeks, tighten the friction 1/4 turn
Repeat until it doesn't squeek

It will squeek occasionally. That's normal.

Do NOT compare your trainer speeds to your outside speeds or anyone else's outside speeds. Only compare this year's trainer speeds to last year's trainer speeds. Trainer speeds tend to be slower to a LOT slower than outside speeds. It doesn't mean anything and your trainer has a sliding scale of resistance so it cannot even be figured out what your inside is to what your outside should be unless you have a power meter and a lot of history with it.

Damn.  I've been turning mine 5 times after contact.  I read that the amount of turns on the tension knob had minimal effect on the resistance.  The manual says 2 to 5 turns.  Just make sure no slipping.  Do a coast down test to stay consistent.

 

what's a coast down test?

Ok, thanks guys.  What you've all said makes sense.  I think I may have had a bit of slippage so I think I have it set a little too loose.  I'm going to reset it again as per everyone's suggestions.  Thanks a bunch!

Amount of time it takes to come to a complete stop.  KK says 15 seconds at 20 mph.  Get the trainer warmed up.  Get up to 20 mph then stop pedaling.  It should take 15 seconds to stop.

http://www.kurtkinetic.com/road-machine-p-35-l-en.html

 

I try to calibrate the tightness on my KK to give a coast down time of 13.4s, which is a value often quoted by folks who have tested their trainer power estimates against PowerTap numbers. For me, this yields a small amount of squeaking when I first accelerate, but none when I'm riding steady. 

http://www.cyclingforums.com/forum/thread/386350/kurt-kinetic-tension-setting

http://www.cyclingforums.com/forum/thread/382859/kurt-kinetic-questions

http://www.cyclingforums.com/forum/thread/446210/advice-on-turbo-trainer-with-reasonably-accurate-power

I think that the 15s coast down time mentioned in the link above is not intended as an accurate calibration target, but more as a ballpark figure for use in advertising the value of the KK flywheel (longer coast down times are generally considered better, as they are more 'road like'). 

I find that the relation between effort and speed reading on the KK is extremely stable from one workout to the next, and I can also predict HR fairly well based on the speed reading on my bike computer. I do not untighten the flywheel when I remove the bike after each workout, so that may contribute to the consistency. When I experimented by loosening the flywheel to raise the coast down time to 15-16s, or tightened it to lower the coast down time to 11-12s (that got rid of all squeaking), I really noticed the difference in resistance. 

thanks for the info.  Im gonna have to try that out.

edit:
just did a quick test.  @ 2.5 turns as I have resistance on.  20mph coast down is about 9.48 seconds. I tried 1 full turn and got 14.96 seconds.  Im still getting a little tire slippage on acceleration.  So Im gonna have to increrase resistance a bit



Edited by astig 2011-02-12 1:00 PM

Perfect info...I will try the coast test today as well, thanks!