Topic: Drive clicking

[mhurt]

Hi all. I got my C5 on Sunday, and have had a couple of quick goes on it - mainly pedalling as I need to build up my leg muscles and stamina (Monday, it took me 10 mins to move 3ft uphill!).

Anyway, I've been really cautious about not using the motor without being at a reasonable speed, and even then only using it in short bursts going uphill, just to ensure I don't cause any damage.
To be honest, all Ive done is on Monday, I took it up the road, down to the bottom, and back home (it is fairly steep though) and on Tuesday I did the same but 3 times.

Today, I took it a bit further, and took it around the block, including down the main road, which is quite a big hill. Everything was great - even if I did have a squeaky bum moment braking in time for a junction on the way down..... I got home and waited 5-10mins while I called the paramedics and ordered the oxygen cylinders

When I set off again, moving downhill, as soon as I touched the power button, it sounded like a hammer drill, so I immediately stopped.
I've taken the drive wheel off and the belt, and everything looks fine there - no cracks that I can see or chips/breaks etc, and the motor is flush with the fence and the belt looks pretty new. Putting it all back together, I did notice some black stuff in between the teeth of the belt, so I've cleaned that out (it felt like putty/soft rubber).
I havent ridden it again yet, but there's no clicking noise when running the motor with the wheels off the ground.

Is there anything else I should check before I try the C5 with a load on the motor ?

Cheers

(Sorry, I forgot to take photos of everything, but it wouldn't take long to strip it down again if needed)
pps. I havent taken the motor/gearbox apart to check inside, as that's a bit beyond me currently.

[kamilb1998]

Take a look at this

http://c5alive.co.uk/forum/index.php?topic=1181.0

[mhurt]

Yup, checked there and a few other threads and everything looks OK.
There's already a cable tie holding the fence in place,. The only difference I can see is that on that thread, the motor is slightly protruding past the fence, whereas mine is flush with it (as in, its sat on the fence but the face of the brown part is flush with the wheel-side face of the fence). Would that make a difference ? If it does, I can move the motor forward by a few mm's.

Cheers for the reply

[kamilb1998]

I don't think it makes a difference, as long as the motor is sitting on the 'fence' it's OK.

Next thing I'd check is the belt tension, you should have no more than 1/4" slack.

[mhurt]

Checked that too - seems pretty tight, probably less than 1/4 but I'll double check in the morning

[kamilb1998]

How old is the drive belt? Do the drive cogs look worn?

Make some marking to double check if it is the drive belt slipping. I had a similar noise to a slipping belt when the little cogs in my gearbox got worn.

[mhurt]

Drive belt looks pretty new. I'll make some markings tomorrow and test. Hope it isn't inside the gearbox as I'm not sure I could fix that.

I'll have a look on the forum for instructions & replacements just in case.

[radiomarty]

The motor should be fully forward - when it is pushed in it will hit a stop in the retaining clamp with no visible gaps(ie as far forward to the drive wheel as possible) - there is one 10mm nut that clamps it in place - if you loosen this to ensure it is fully forward - with the motor loose you can also check tension to the belt by twisting if forwards or backwards. Ensure it does not fall of the fence while adjusting it.

You need to check your drive cog - take of the drive wheel and have a good look at the output cog and the drive cog on the axle for broken teeth or uneven wear  - ideally take the belt of for checking by twisting the motor to reduce tension.

If all is ok it could be worn or damage to the parts inside the gearbox or worst case the armature has snapped at the top end where the two small bearings sit

Take it stage by stage and take some photos and we will try to identify the fault

Marty

[mhurt]

Hi,

I tried the C5 yesterday, and went around the block perfectly OK until I got to a point uphill where I had to pull in to let a taxi through. As I was struggling to get moving again, I accidentally caught the power button and immediately got the clicking (as expected, there's no way I'd try to use power in that situation), and after that it wouldn't move again - I just got the hammer drill effect.
I immediately pushed it home and took a look (photos below). After re-assembling, the motor is running fine with no load.

Looking at things, I think it might just be belt slip, but as I'm new to this, I'd rather have a second opinion. So, here are the photos :








I think the black stuff is rubber from the belt and it clogged up a bit, causing the sound & loss of drive ?


And hopefully this shows the belt tension : http://www.flickr.com/photos/33460912@N05/7669995558/

Hope I've taken shots of everything needed.

Cheers

[kamilb1998]

Those gearbox teeth look a little worn but whether they're worn enough to warrant belt slip, I don't really know.

[Karl]

The drive belt is toast and needs replacing.

The bodge job on the gearbox cog suggests the belt slip has been taking place for quite some time , long enough for someone to have a go at trying to cure it 

My advice would be to replace the drive belt and make sure the motor is properly set up i.e. (as Marty says) pushed fully into the motor mount as if you are trying to push the motor into the rear wheel and then make sure it is rotated correctly before everything is tightened up . When rotating the motor, start so that the heat sensor ( black clip on flat part of motor with orange wire) is at the lowest part. Then rotate the motor until a good belt tension is achieved , this shouldn't be that much - mine have all been set up with this sensor pretty much still at the lowest point. Then make sure the "fence" is sorted , as shown ealier in this thread.

[mhurt]

OK, thanks for that.

I'll order a belt from the main page and get it fitted as per the instructions. I'll also save up towards one of Chas's metal gearbox inserts just for good measure!

Really appreciate the advice. Hopefully, at some point I will be competent enough to help others & give something back.

[C5 ENTHUSIAST + RESTORER]

Hi there as it's all  been said the gearbox teeth are worn 'also the belt needs replacing ..The next thing is to check out the armature to see if has snapped off The part that holds the small bearings inside the gearbox ...Be careful if you are attempting to take the gear box off as the fingers may break off  ...

[mhurt]

Thanks everyone.
I'll get a new belt, move the motor forward and tighten and see how it goes. With luck, it will last until I can afford a new motor or a metal replacement.

[mhurt]

The new belt seems to have done the job, based on a few times around the block. After looking at photos of new gearboxes and then mine, I will definitely save towards a new motor/gearbox or metal insert.

Thanks to everyone that helped.