Adjusting belt tension?

Addendum:

Ah - the Strida 3 has a different system to the 5 and its copies. The manual is online here and P 28 tells you how to do it.
http://www.strida.us/files/strida3.pdf

It seems that you loosen the bolts that hold the BB unit onto the frame and then turn an adjuster on the backside of it. I expect you know this and have done it already. If the adjuster bolt pulls the BB forward by being threaded into the frame tube, you WON’T get anywhere by tapping it forward or backward either, because the bolt will be holding it in a fixed position.

Hi Ben,

The nut of the belt tensioner of Strida 3 is supposed to be tight in any situation.

If you want to tighten the belt, you have to rotate the nut clockwise after removing the belt from the front pulley and lossen the 4 bolts on the BB moulding. After you have adjusted the nut, you have to retighten the 4 bolts and put the belt back onto the front pulley.


Cheers

Amuro

Sorry to resurrect this thread, just a quick additional question … anyone happen to know exactly what size c-spanner would be required? (FYI, this is called a “Hakenschlüssel” in German. :slight_smile: )

Help!!! The big ring on the LH side is not loosening at all (I am using the metal rod method and I am afraid that I am going to start taking big chunks out of it.) :blush:

Can someone please confirm which direction is loose and which is tight? I assumed counterclockwise to loosen it, but then I wondered if it is threaded in the opposite way, like the left hand pedal normally is??

Yes- its standard Right hand thread.
now I will TRY and attach pictures (the in use picture is tightening the ring)

Oooops … how do you attach a pic ?

Luckily, google pictures shows…
similar application
faq.f650.com/FAQs/Photos/Steerin … ighten.jpg
(this is tightening the ring)

and universal c-spanner … (say 1 to 2" in size) …
dkimages.com/discover/DKIMAG … ber-1.html

Here is a BBcode guide on adding images to a post:
http://www.stridaforum.com/forum/faq.php?mode=bbcode#f50

Or you can just use the “upload attachment” function available in this forum to upload and attach image files directly on the post. :wink:
http://www.stridaforum.com/forum/faq.php#f33

Thanks - it would be nice to be able to upload a pic from a pc to here, rather than uploading somewhere else and linking to it … or have I missed something ? but this is not a big issue.

sorry for interlude - now back to belt tensioning

As a follow-up, I was able to find a mechanic with a c-spanner. Couldn’t find one to buy anywhere – only some of the bike mechanics had even heard of it. Apparently it used to be needed for a lot of bikes, but nowadays the manufacturers have custom wrenches that fit exactly to the specs of their ring. (What exactly is this ring called, anyway?) I ordered the tool for myself, but the mechanic had to look through 4 different catalogs before he found it!

(An interesting aside to this whole saga is that strida.nl sent me this reply after I’d already managed to loosen the ring:

)

Anyway, my belt is now tighter and there is less popping, but not no popping. Looking at the freewheel, I fear that this could be due to wear. The teeth are all supposed to be straight across, are they not? On my freewheel, several are concave. It is also interesting that with the belt tighter, there is some “rear-end wobble” that I hadn’t noticed before.

Maybe I should revisit the snubber. That leads me to a new question. On the 5.0, there is a disc (of course, since it has disc brakes) that makes it quite hard to get at the bolt head of the snubber. Should I just try to find a really flat wrench, or do I need to take the wheel apart?!

Those C-Spanners are not necessarily bike tools - I got mine from a general hardware store, I think the ‘ring’ could be called a ‘lock ring’ ?

Snubber gap to back of belt should be as small as possible without being in constant contact with the belt. 0.25mm would be about right 0.75 or 1mm too big. If you belt has been running with loose snubber and tension for some time (ie regularly popping) it may be possible you have damaged a few kevlar cords - reducing the belt’s stiffness and so making it more prone squeezing past snubber, and so jumping more than a new belt would do.

I find a THIN flat spanner is best the get to head of snubber between it and disc – OR a slim socket through the disc. Adjusting the snubber to get the be optimum 0.25mm gap is fiddly … I seem to need 3 hands !! (1/2" / 13mm Spanner for head, 0.25mm feeler gauge / plastic strip to set 0.25mm gap, and another 11mm spanner for the lock nut ).

If all goes well your belt will not ever jump - good luck (this message will self destruct in 3 minutes :smiley: )

Hi Human Amp,

It is possible to attach photos on how to lossen/tighten the snubber head to get the 0.25 mm gap? I have problem finding the right bolt and nut though you have provided a quite detailed explanation.

Thank you very much.

Hey - check out
and

and if these don’t work … try whole new ‘Strida Tech album’
http://picasaweb.google.co.uk/Human.Amp/StridaTech#

Dear Human Amp,

Thanks. Will try it out. :smiley:

I have no idea why, but today I started to get the ‘popping’ sound on hills that tells that the drive belt is too slack. I pushed it uphills so as not to wear the pulleys by slippage and rode it on the flat until I got back home. The SLO has been ridden about 250 miles and never a ‘pop’ until now really and when I investigated, the BB was tight and seemed well secured by the adjustment hex screw. I suppose it might be possible that some mighty torque applied by me on a hill made the BB slip around even though the securing / adjustment screw remained seemingly secure, but I don’t feel it is likely. Another possibility is that the rather warmer temperatures of today have made the belt expand (it is 10c here now, and the bike has been ridden in somewhat cooler temperatures of around -3C to about +5C). However, the belts are not supposed to react like that. Kevlar has a strange negative expansion when warmed. The belt is supposed to be kevlar reinforced, so that shouldn’t happen if it’s true.

Anyhow - I adjusted it and all seems well now, but I don’t have a lot of adjustment left if there is any more expansion. Nothing else can move as far as I can see, so either the belt has stretched or expanded, or the BB slippped around.

Perhaps the problem is at the other end … Does the freewheel have any signs of wear on the teeth? And what about the snubber, does it still have a small enough gap?

I posted in the tech forum as i have also had problems adjusting the tension bolt. To add to this ive just found out that Strida i have is in fact a fake one; a Ming Tai.

Does the Ming Tais have the same C-spanner tension adjustment?

Ive just noticed that Ming now own Strida so it is an official one??

Well ive looked through this post and used a hammer and screw driver to knock that BB back. Nice tight belt :slight_smile:

Sorry for bringing up at old thread … on my strida 5, i managed to loosen the ring but still not able to move the nut to loosen my belt tension

Any other suggestions?

No reason to be sorry :smiley:

If you loosened the “ring” (equal to lock ring, groove nut or the part 5 in the rectangle 130-00 shown at the detailed parts drawing, page 12 of the manual) - which part do you mean with the nut?
Strida manual

Hi,
I was trying to slide/move part 274 after loosening part5 of section 130-00.
No matter what i do …the screw 274 does not move in any direction

Hello RLCH,

please try it like that:
Remove bolt 274 completely, after that insert a drift punch into the thread and move the bottom bracket excenter:
(Disregard the arrows and the Allen key shown below.)

Caution: Do not insert the drift punch too deep at ATS or Schlumpf speed drives - otherwise you might damage the shifting axle which is located inside of the bottom bracket axle!