Strida 5 - Front pulley and freewheel

Strida Forum Strida Problems and Answers
1

Hello,

I am a new owner of a Strida 5 and I would like to get your inputs on the following :

  1. My front pulley (where the pedals are attached) is slightly buckled. I can see that by looking from the top when the pulley is turning quite fast (it goes from side to side). I understand that, this pulley being in plastic and with a big diameter, it would be very difficult to get a perfect flat disc but I would like to know if you have the same issue

  2. If find the rear freewheel to be not “free enough” when compared to a “classic” bike. For instance the free wheel action on a classic bike last much longer than on the Strida. Which means the efficiency of the free wheel is lower on the strida.

Did you notice the same ?

Thanks a lot for your answers.

2

Hi there

I’m a recent Strida 5 rider, after one year of riding a Strida 3.

The ‘pulley’ you mention at the front (on a standard bike I guess you mean the chainring), is this buckle apparent when you are cycling or just when you rotate by hand and observe?

The reason I ask is that I found the amount of flex in the bottom bracket, crank and chainring (beltring!?) on the Strida 3 was considerable, particularly when pushing the pedals hard. On my strida 5 I can see that just the beltring (pulley) does still flex a little. In both instances I think the downward pedal pressure puts enough strain on one point to flex it a little. If you are experiencing the flex during normal cycling I would assume this is perfectly normal - but that’s just my take on things!

On your second point, yes you are right - the efficiency of the unlubricated kevlar on plastic freewheel is not as high as a well oiled metal chain and cog. The belt tension necessary to stay on the cog under pressure means a bit of friction. I found the Strida 3 belt drive used to ‘pop’ off the rear cog quite a bit if I pedalled really hard (say on a small hill), but this seems to be solved on the Strida 5.

Not sure if that helps?

3

Welcome - another triangle

I agree with deck44 … front pulley does seem to flex when under pressure, and even when spining when not underr load I would expect up to say 2mm sideways movement. Anymore I would want to investigate … is it a slightly warped pulley (eg left out in the sun propped up against a rock ??) OR the mounting screws are not all equally tightened … if so you could try slackening all 4 off and gradually re-tightening.

At the rear, Have you checked that the snubber bearing (round the back of the rear pulley) is not in constant contact with the back of the belt … it should have a small gap (about 1/4 mm), so that it only comes into contact with the belt at extremes, eg setting off etc. Also if the belt tension is too high it can give a little more drag… thats adjusted at the front - eccentric crank axle.

4

Hello Deckfourtyfour,

Thank you for your answers

  1. Yes I mean the chainring (ie beltring in that case) (I am french and my bike english vocab is not that strong …). I observe the buckle when I rotate by hand. Is yours perfectly flat when you rotate with the rear wheel in the air ?

  2. Sounds fair

Have a nice day

5

Cheers for the welcome. Good to be onboard.

Poder1 - I just checked my Strida 5 (by holding it and spinning the pedals in the air) and my front pulley is also not completely straight. It has a slight ‘wobble’ in it. I haven’t noticed this before!

6

Human Amp, thanks for the tip, I will unscrew the pedal from the chain ring and carefuly screw it back to see if that helps.

DeckFourtyFour, The plastic the belt ring is made of is certainly reinforced with glass fibers. Thus given the large diameter it is very difficult to mold a perfectly flat disk (anisotropic shrinkage during molding). This part should be made out of metal but I guess the wearing on the belt should be higher then.