Kurt Kinetic computer

[kant314]

Hi guys,

I'm just about to put my damn KK trainer on ebay...I've just about had enough of it.
Don't get me wrong, I love the trainer. It has a great feel to it.
It's just the bloody crapy power computer they sell with it. £25 for something that looks like it was made in China in the 70's.
I've already sent 2 back and I'm on my third now. After a few weeks of use these things just seem to begin to go wrong.
The first one I had the buttons kept sticking so that you couldn't change the display screen without resetting everything. Then it started blanking out and going back to zero in the middle of a session. The 2nd one they sent me was dead on arrival and the third one resets the tyre calibration size half way through a session and changes to km/h. That's if it makes it through a 20 min session at all.

I real really wish I'd gone for another trainer with power.

I'd heard bad things about the KK power computer before I bought it but TBH I thought it really can't be that bad.

How wrong I was.


(rant over)

 

[fleshbroiler]

I was fairly disappointed when I got my KK computer and discovered how cheesy the thing is for the price. Mine ate batteries but always functioned. I killed it by accident when the chainstay sensor shifted position while out on the road, resulting in amputation. If you like the KK, just buy a cheap rear sensing cycle computer.

 

[LT Intolerant]

I'm just about to put my damn KK trainer on ebay...

If you REALLY want to frustrate yourself I have a TACX Fortius for sale at a great price.

 

[Piotr]

If you REALLY want to frustrate yourself I have a TACX Fortius for sale at a great price.

I used the little computer on my KK up until I got Powertap a year ago and it had issues too. IIRC, it wouldn't work if it was snapped "correctly" into the cradle. I had to pull it out slightly to make it work. Just print Wiredued's conversion list, paste it on a wall next to you while training. You'll have it memorized in no time. Or, make your own spreadsheet using this formula:

Power = (5.24482*Speed) + (.019168*Speed^3)

 

[kant314]

I used the little computer on my KK up until I got Powertap a year ago and it had issues too. IIRC, it wouldn't work if it was snapped "correctly" into the cradle. I had to pull it out slightly to make it work. Just print Wiredued's conversion list, paste it on a wall next to you while training. You'll have it memorized in no time. Or, make your own spreadsheet using this formula:

Power = (5.24482*Speed) + (.019168*Speed^3)

thanks, that's a pretty cool idea.
Does anyone have any recommendations for a rear mounted computer?
I think I'll ditch the KK comp.

 

[Ade Merckx]

Hi guys,

I'm just about to put my damn KK trainer on ebay...I've just about had enough of it.)

Whoa!! slow down there fella. Don't throw the baby out with the bath water. You've joined the 300watt club you're comfortable in the ACC 19s things are going well...The CTC Hilly was cold to start off with but warmed up and was a lovely day...The weight will come off when you start the longer rides

Finally just get another "computer" like others have said. My 2nd KK computer is still going well, I lost the first one doing thru and off on the dual carriageway. I haven't been able to read your blog for a while cause its keeps saying I'm not invited or something. I'm glad things are going well. Have you tried a 3 x 30 on the KK yet thats a lot of fun

 

[kant314]

Hi Ade,

I didn't mean I was going to stop training...LOL
Just that I'm sick of the KK computer going mental on me.
BTW, I'm on my third one since November.

I think I'll do as you suggest and get an ordinary rear wheel sensor comp and just deduce the wattage from the average speed.

Sorry you couldn't access the blog....not sure why that was. I'll check the settings on the blog page.

Not tried a 3x30 yet. Maybe if this cold weather keeps up I'll knock one out next weekend
cheers
John

 

[Ade Merckx]

Hi Ade,

I didn't mean I was going to stop training...LOL
Just that I'm sick of the KK computer going mental on me.
BTW, I'm on my third one since November.

I think I'll do as you suggest and get an ordinary rear wheel sensor comp and just deduce the wattage from the average speed.

Sorry you couldn't access the blog....not sure why that was. I'll check the settings on the blog page.

Not tried a 3x30 yet. Maybe if this cold weather keeps up I'll knock one out next weekend
cheers
John

cool, you've made pretty impressive gains. How many hours are you doing on average per week. Oh and I think you're gonna be fine when it comes to racing

 

[kant314]

cool, you've made pretty impressive gains. How many hours are you doing on average per week. Oh and I think you're gonna be fine when it comes to racing

well, it kinda depends on work commitments at the moment.
I cycle into work in the city, which is about 10 miles each way, but that's by no means training since I tend to go really slowly and get over taken quite a lot by fat mountainbikers with panniers. I'm not into all this commuter racing

So I just twiddle along in the small ring.
My typical week I'll do 2 turbo sessions maybe on Tues and Thurs and get out on a club run once or twice a month. So, not a lot of hours really.
I've got no problem about missing a session here and there if I'm feeling tired.
I reckon at my age it's better to rest rather than push yourself too much

 

[wiredued]

Yup the KK computer is **** FWIW IMHO the KK Rock and Roll Pro is **** too... OTOH The Kurt Kinetic Road Machine is the best trainer in it's price range if you don't have Computrainer money I would keep it.

Hi guys,

I'm just about to put my damn KK trainer on ebay...I've just about had enough of it.
Don't get me wrong, I love the trainer. It has a great feel to it.
It's just the bloody crapy power computer they sell with it. £25 for something that looks like it was made in China in the 70's.
I've already sent 2 back and I'm on my third now. After a few weeks of use these things just seem to begin to go wrong.
The first one I had the buttons kept sticking so that you couldn't change the display screen without resetting everything. Then it started blanking out and going back to zero in the middle of a session. The 2nd one they sent me was dead on arrival and the third one resets the tyre calibration size half way through a session and changes to km/h. That's if it makes it through a 20 min session at all.

I real really wish I'd gone for another trainer with power.

I'd heard bad things about the KK power computer before I bought it but TBH I thought it really can't be that bad.

How wrong I was.


(rant over)

 

[no1kung1]

Echoing what others have said. In my experience (I own two, the standard KK and a KK Rock and Roll Pro) Kurt Kinetics are really great trainers. Super heavy duty and dependable. Customer service is also great.

However, like you said the power computer is a joke. I had problems with mine also after dropping it. They quickly replaced it free of charge, but I opened up the old one to see if I can fix it. They use a VERY flimsy method of passing the electrical signal through to the screen. It is essentially two small rectangular pieces of foam that have conductive channels that sit on the top and bottom of the screen. They are barely glued into place and if they ever move out of place, realignment is a nightmare. Just get a standard cyclo computer that reads speed, you'll be able to use it outside without having to ignore the giant power number. Just look up from the previously provided charts the corresponding powers to the zones you want to target and use that.

 

[kant314]

thanks guys.
Good advice

 

[phantoj]

I used the little computer on my KK up until I got Powertap a year ago and it had issues too. IIRC, it wouldn't work if it was snapped "correctly" into the cradle. I had to pull it out slightly to make it work. Just print Wiredued's conversion list, paste it on a wall next to you while training. You'll have it memorized in no time. Or, make your own spreadsheet using this formula:

Power = (5.24482*Speed) + (.019168*Speed^3)

I think wiredued's conversion list is based on the formula:

Power = (5.24482*Speed) + (.01968*Speed^3)

incorporating what appears to be a typo from the Kurt Kinetic website.

Compare to the chart at: http://www.kurtkinetic.com/documents/Power_Curves419.pdf

Hmm, wait, they agree... never mind, carry on.

 

[kant314]

I think wiredued's conversion list is based on the formula:

Power = (5.24482*Speed) + (.01968*Speed^3)

incorporating what appears to be a typo from the Kurt Kinetic website.

Compare to the chart at: http://www.kurtkinetic.com/documents/Power_Curves419.pdf

Hmm, wait, they agree... never mind, carry on.

Is that speed in the formula in mph or km/h?

 

[Itchy-Tichy]

Is that speed in the formula in mph or km/h?

From the KK website:

Remember algebra? Good. The formula for the Cyclone and the Road Machine turns out to be a cubic function. If we let S stand for “speed” in miles per hour, and P stand for “power” in watts, the formulas are as follows:

Kinetic Cyclone:
P = (6.481090) * S + (0.020106) * S3

Kinetic Road Machine:
P = (5.244820) * S + (0.01968) * S3

For example, to calculate how much power is produced at a speed of 16.1mph while riding the Kinetic Road Machine, plug 16.1 in for “S.”

P = (5.244820) * (16.1) + (0.01968) * (16.1)3

P = (5.244820) * (16.1) + (0.01968) * (16.1) * (16.1) * (16.1)

P = 84.4416 + 82.13017

Power = 166.571 watts

 

[kant314]

From the KK website:

Remember algebra? Good. The formula for the Cyclone and the Road Machine turns out to be a cubic function. If we let S stand for “speed” in miles per hour, and P stand for “power” in watts, the formulas are as follows:

Kinetic Cyclone:
P = (6.481090) * S + (0.020106) * S3

Kinetic Road Machine:
P = (5.244820) * S + (0.01968) * S3

For example, to calculate how much power is produced at a speed of 16.1mph while riding the Kinetic Road Machine, plug 16.1 in for “S.”

P = (5.244820) * (16.1) + (0.01968) * (16.1)3

P = (5.244820) * (16.1) + (0.01968) * (16.1) * (16.1) * (16.1)

P = 84.4416 + 82.13017

Power = 166.571 watts

so what you're trying to say is that the formula is for MPH.

 

[wiredued]

Keep in mind the the number entered into the computer is 1917 which corresponds to .019168 Piotr had to correct me about a year ago because I took the typo formula from the KK web site.

From the KK website:

Remember algebra? Good. The formula for the Cyclone and the Road Machine turns out to be a cubic function. If we let S stand for “speed” in miles per hour, and P stand for “power” in watts, the formulas are as follows:

Kinetic Cyclone:
P = (6.481090) * S + (0.020106) * S3

Kinetic Road Machine:
P = (5.244820) * S + (0.01968) * S3

For example, to calculate how much power is produced at a speed of 16.1mph while riding the Kinetic Road Machine, plug 16.1 in for “S.”

P = (5.244820) * (16.1) + (0.01968) * (16.1)3

P = (5.244820) * (16.1) + (0.01968) * (16.1) * (16.1) * (16.1)

P = 84.4416 + 82.13017

Power = 166.571 watts

 

[wiredued]

It is in mph but if you ad a column on the left to an Excel sheet for kph with the formula to convert to mph you could get kph easy enough.

Is that speed in the formula in mph or km/h?

 

[frenchyge]

Keep in mind the the number entered into the computer is 1917 which corresponds to .019168 Piotr had to correct me about a year ago because I took the typo formula from the KK web site.

D'oh! I thought I remembered there being a typo involved in there somewhere.

I recently had to send my PT hub in for repair and have been using the speed curve for the past couple weeks when I discovered that my hub had been reading about 35w below what the speed *formula* would predict. I remembered some old conversation about that formula, but couldn't remember what came of it since I normally use my power hub. Looks like those extra 35w aren't coming my way after all.

Edit: Hmmmm..... difference is only a couple watts (between the two formulae). Hopefully they'll calibrate my hub while they have it.

I wonder if Kinetic uses a rolling resistance on that curve, or if that's purely the power to drive the unit? Could mean another 10-20 watts at the cranks for all the 300w-club hope-to-bes.

 

[wiredued]

I think it only dropped my FTP by about 4 watts when I made the correction.

D'oh! I thought I remembered there being a typo involved in there somewhere.

I recently had to send my PT hub in for repair and have been using the speed curve for the past couple weeks when I discovered that my hub had been reading about 35w below what the speed *formula* would predict. I remembered some old conversation about that formula, but couldn't remember what came of it since I normally use my power hub. Looks like those extra 35w aren't coming my way after all.