Handle bar problem

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Hi all more question I'm afraid.

Friend of mine lent me his sons Scirocco cd woosh bike. he no longer needs an ebike as he has got himself fit enough to ride a regular bike, and was thinking about maybe buying it from him.
There are a couple of issues which I wonder if any one else has come across.
First is quite scary, The handle bars and stem fall forward if I have to brake. They are labelled Promax, I have looked at the allan bolts each side, 2 of, but they seem very very tight. If they are not repairable what is a good replacement?
Also occasionally when pedalling, the chain seems to give a click and i slight mis pedal, every now and then, do you think this is a gear alignment thing or do you think it is the motor gearing?
Aprt from that I have found it a great bike for covering distance, and hills are flattened.
Thanks

pedelecvirgin.
 
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trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
the bolts are very tight when the lever is down. While adjusting the clamp, keep the lever up.
try to locate the source of the click. It could come from the 8-speed cassette. You can get a new cassette from CRC:
http://www.chainreactioncycles.com/shimano-acera-hg41-8-speed-mtb-cassette/rp-prod68154

how to adjust the promax adjustable stem:
release the handelbars, check the teeth stem side and handlebars side
if the teeth are too worn, you can get another one from sjs:
http://www.sjscycles.co.uk/promax-1-1-8-ahead-adjustable-stem-with-qr-10- 90-deg-254mm-clamp-110mm-prod25833/

there are two allen bolts, under the stem, that adjust the clamp.
1) lift the lever up to release the mechanism.
2) tighten the one in front of the handlebars, closing the front gap.
3) tighten the allen bolt nearer to the quill until the bar feels just snugly fit.
Don't over do this, too tight and you can't clamp the lever back down again.
4) adjust the bars position then clamp it and lock it.


 
Last edited:

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Hi thanks for that quick reply. Will try an pay closer attention to the click, but it is so infrequent, it happens unexpexted like, but thanks for the link to new cassette.
Think it needs to be a new adjustable stem, as have tightened all and it still happens seems to be from the lower piece that it folds (it is the bit with the plastic covers on with the 2 allen bolts each side).
Again thanks for the link for replacement part. Will let you know how it works out, but it puts me off a bit. He says only a year old with less than 400 on the clock, is that not a bit soon for this to wear out?seems nothing lasts for long these days.

pedelecvirgin
 
D

Deleted member 4366

Guest
It's not a case of everything being tight. You have to loosen it, then turn the adjuster screw, then tighten everything, then clamp the handlebars. It's only a matter of adjustment.
 

neptune

Esteemed Pedelecer
Jan 30, 2012
1,743
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Boston lincs
The Scirocco CD is a budget bike, but as far as i can see represents excellent value for money. The handlebar stem might need replacing, but who knows what its past history is , it might have suffered abuse. Don`t judge the whole bike on the strength of a faulty handlebar stem. If you can`t find the source of the click your local bike shop may help. This might be caused by a stiff link in the chain. Invert the bike, or hang it up so the back wheel is off the ground.turn the pedals forward, watch the chain as it enters the jockey pulley part of the rear derailleur. Look out for a link that does not bend as it should. A stiff link can be cured by lubrication and bending back and forth until it frees off.
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
pedelecvirgin, please post a picture of the promax stem so we can see what the problem is. The Promax stem is made to clamp 25mm to 27mm diameter handlebars and has quite a wide range of adjustment, you can see by the gap on the side of the clamp. When the lever is up, the gap opens, when the lever is down, the gap closes. Make sure that you keep the lever up when you tighten the allen bolt in the middle. There should not be any need to replace it.
 

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pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Thanks all. I do appreciate that there is more to it than just tightening everything. I may be a pedelecvirgin, but not a bicycle virgin.
It was that I have not come across this type of handlebar stem before and needed some advice. Following all of your comments I will return to the problem tomorrow. And let you know if I can sort it. As i said in second post it is not just the handlebars but the whole stem which slides forwards and down.
trex I will try and post picture tomorrow before and after.
I appreciate the scirocco may be a "budget bike" . I haven't bought it yet, just trying it out to see what I think.
Will probably return to my "budgeter bike" the cyclamatic power plus.
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
this type of QR adjustable stem has become quite popular over the last three years or so. You can adjust quicly to give yourself a more comfortable riding position. For example, change the angle of the brake levers or arm reach, quite useful on MTBs. You see them on a lot of bikes nowadays, Volt, Wisper, Freego, Kudos etc all have some models with them. Some people prefer the non QR version though.
 
D

Deleted member 4366

Guest
As i said in second post it is not just the handlebars but the whole stem which slides forwards and down.
We fully understand that. There's two clamps: One on the handlebar, which stops the handlebar from rotating, and one on the bit that allows the stem to rotate forward and down and back and up. Your task is to adjust the tension on the latter so that it grips tighter, thus preventing the stem from rotating.
 

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Hi sorry for being a tad defensive, I will definitely follow your guidelines tomorrow evening, and see if I can spot what I am not doing.
 

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Sorry not to get back yesterday, but decided to sort bike and then gor a quick ride, turned into quite nice 2 hr outing.

Thank you for all your help after stopping and looking through the postal replies I was able to identify, the two bolts which needed adjusting. I successfully adjusted them, and am now able to ride without the movement of the handlebars. So again thanks for your replies.

I still have the problem with the clicking sound, only when the power is on, did about 3 miles with no power, no click, as soon as I turned power on The click returned. I will try and get the bike off the ground and look and listen carefully to where the noise is coming from.

It is not just limited to apply pressure i.e. when going up ab incline, it is also when pedalling on the flat.

Thanks again

pedelecvirgin
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
does the click come in when you use only the throttle?
 

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
No It may be a little more pronounced when using the throttle, but both with and using assist at all levels.

pedelecvirgin
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
How many clicks per revolution of the cranks?

No It may be a little more pronounced when using the throttle, but both with and using assist at all levels.

pedelecvirgin
You said earlier that the click disappears when cycling unassisted, that rules out the pedals, cranks, chain, cassette, pedelec rotation sensor, sprag clutch as possible source.
 

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Not continuous, probably more so if I stop pedalling, and then restart.

Hope fully I will be able to do a proper count and instances when it occurs, and report back you with more detailed info.


pedelecvirgin
 

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
Okay so to continue, went on bike today. The crunching/clicking noise only occurs under power. It does not occur on every revoloution of the pedals. It is not confined to harder pedalling, it will occur at the bottom of a revoution i.e. as the motor stops/disengages. The feel of it is,is as the motor engages, so it is more noticeable. It happens less obviously when going at speed. It is not confined to any assist level. It is not confined to a particular gear, but is less obvious when in a lower gear.
Don't know if this helps with any form of diagnosis. The bike still gives good mileage, good assist, I just don't want it to fail on me, whilst I am out.

Thanks.

pedelecvirgin
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
it will occur at the bottom of a revoution: do you mean when the cranks are at 12 o'clock or 6 o'clock?
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
first, you need to check that the crank bolts are tight.
For this, you need a long handle 8mm allen key like this one

Tighten each bolt about half a turn to see if the click changes.

the torque setting for these two bolts is 40NM-50NM, quite high. The bolts also has to have some medium strength blue loctite to stop them getting loosened.

 

pedelecvirgin

Pedelecer
Jun 15, 2013
38
3
New wrench bought, blue loctite bought, bolts removed cleaned, blue loctite applied as per instructions, tightened to 45 Nm. No difference whatsoever.

pedelecvirgin