Schwinn I Zip / Canadian Tire Bike / Rear Hub Bearing

[GTA1]

I think the wheel bearing on my Schwinn I Zip with the side mounted motor has loosened or worn.

I can push the wheel left and right at the rim and feel a bit of play.

Off hand, it looks like it is pretty involved to remove the rear wheel.

Does anyone know what is the standard procedure to remove the wheel and adjust the hub bearings?

Will I need the tool to remove the gear cone? Or can the wheel bearing be tightened on the other side (the motor driven sprocket side)?

Thanks!

 

[c_4]

Yep, those i-Zip rear bearing assemblies are extremely prone to wear... In my case, I tried tightening the right-hand cone nut after loosening the right hand axle bolt and flexing the frame away from the wheel to give myself a bit of room to work- this had limited success and the play returned after just a couple of weeks and this time there was quite a bit of rolling resistance.. It turned out that the right cone nut itself was worn and mangled pretty badly and had to be replaced along with the bearings.. Replacing the bearings worked for about a year, and then the play returned- again, new cone nut and the bearing surfaces on the hub itself were showing some minor signs of wear this time and probably should have been replaced- issue here was the motor drive sprocket on the left side: you need a hub that is threaded on the left hand side as well, and I could find anyone who had this part, so I just put new bearings and another set of cone nuts and this time I put in molybdenum grease- this seemed to have stopped the wear in its tracks as I ran it more than a year before I converted the bike over to an eZee rear hub, and when I removed the old wheel, it was still nice and tight..

The rear wheel definitely *IS* a major pain to remove: perhaps someone else has discovered an easier method, but the 4 times I had to remove the wheel (once to fix a flat, twice for bearings, and the last time to replace the whole rear wheel with an eZee rear hub kit), the easiest method I found was to remove the 3 or 4 bolts holding the motor to the frame, and then pull out the motor so that the left-hand chain can come off, then you have to loosen and then remove the tensioning bracket on the left side, and then finally, you can just loosen the right hand nut and the wheel can slide out of the dropouts..

The wheel itself is easy to service once out: remove the freewheel with a standard spline adapter and then two wrenches to loosen and remove the jam nut and the right-hand cone nut. The bearings are held in a little sheet-metal cage, so they are reasonably easy to manage. The axle pulls right out of the left side, so you can replace the left hand set of bearings as well without removing the left hand motor drive sprocket.

 

[GTA1]

Hey, thanks for the tips...

I had this nagging suspicion it is not so simple as to just tighten the bearings.

The right bearing is the power bearing --- load from the motor goes right there so it is expected to be highly stressed.

Where did you get your replacement bearing and cone set from? Is it a regular bicycle grade or did you get a motorcycle grade part?

Now that I know the bad news.... I may stick the manufacturer with the work under the warranty.


Here is a silly question:

China is the world leader in low to mid end electric bikes.

How can it possibly be that a electric bike have as obvious a wear part fail as a set of bearings and cones UNLESS the maker of this bike (whoever Dorel imports from) is a cut rate export maker and this model is NOT one of the mainstream Chinese bikes that basically are designed to be used far more intensively than any bike in the US?

It cannot possibly be made by one of the big Chinese e bike names....

Anyone know who is the real maker of the 2008 Schwinn i-Zip?

Let's tack this company on the dud list...

 

[TylerDurden]

China is the world leader in low to mid end electric bikes... How can it possibly be that a electric bike have as obvious a wear part fail as a set of bearings and cones UNLESS the maker of this bike (whoever Dorel imports from) is a cut rate export maker and this model is NOT one of the mainstream Chinese bikes that basically are designed to be used far more intensively than any bike in the US?

It might not be a surprise that a manufacturers in China sell crap to their pointedly un-marketsavvy domestic consumers.

 

[c_4]

Regular bike cone nuts/ball bearings from a good bike shop.. There was nothing at all "heavy duty" or non-standard about them..

You might want to use moly grease as well to help with the higher load and wear..

The bike wheels/hubs/bearings are definitely cheap stuff, but the steel frame is actually quite well reinforced, which is why I decided to keep the frame when I upgraded to a hub motor.. Along with the Ezee hub on the rear, I also put a matching Schwalbe Marathon Plus tire on the front with a good Mavic rim and the difference in ride with the better tires, and the reduced weight from losing the SLA battery and that heavy outboard motor was just amazing..

 

[GTA1]

The bike wheels/hubs/bearings are definitely cheap stuff, but the steel frame is actually quite well reinforced, which is why I decided to keep the frame when I upgraded to a hub motor.. Along with the Ezee hub on the rear, I also put a matching Schwalbe Marathon Plus tire on the front with a good Mavic rim and the difference in ride with the better tires, and the reduced weight from losing the SLA battery and that heavy outboard motor was just amazing..

Did you have to replace the fork?

The frame is indeed well built --- though I am now pretty firmly of the opinion that e bikes built for 50kph should have good quality front and rear suspensions.

I am finding that the front wheel / spokes or the forks are definitely bending under the strain. i.e. when I corner, I can feel the wheel rim bending (and rubbing against the brakes).

The alternative to a rear suspension would be a much larger tire / smaller wheel --- a moped / motorcycle grade tire that have much more "give" and can absorb more of the shock from the road.

 

[c_4]

No, because I converted using a rear hub, I left the front fork, just replaced the wheel/tire to match the rear; the fork is a Zoom, which is sort of the de-facto industry standard OEM suspension fork that you see on just about every entry-level bike and while it's not super, it's not horrible either.. The bike is designed using a narrow quill steerer, so my alternatives for replacing the fork would be to convert to non-suspension rigid forks (not for me), special order something (and about the only replacement available other than another Zoom is from RST and it's the same spring-polymer type that the Zoom is, and pretty similar quality-wise), or to convert/replace the headset to a threadless, which would give me access to gas/oil-filled suspension forks, but since I like my handlebars set up quite a bit higher than most people, the extra work required to convert a cheap bike frame, the lack of easy height adjustability of most threadless sets, which have to be cut to length and stacked with spacers, was just not appealing to me, not to mention that I'd already spent a fair bit on the rear hub kit and also a new front tire and rim, so I really couldn't justify another $400-500 on top for something that didn't really need to be replaced..

I'm not sure I agree about rear suspension, at least not 100%: while I do think there should be something to compensate for the extra weight of the motor/battery pack in the back, I don't think the rear suspension of the popular style with the hinge and spring in the middle of the bike is the right solution.. WIth a rear hub, when you accelerate on the motor, this sort of bike suspension allows it to basically "fold up" and tip the seat, especially with a high torque motor.. If you adjust the spring tension to prevent this, then it's so rigid as to not make much difference vs a "hard tail" over road bumps.. Other than going for some sort of independent rear suspension with dual shocks like you have on motorcycles, I can't really think of a way to make a "safe" e-bike rear suspension..

 

[GTA1]

The only way to get a good suspension system for a e bike is to build one from the ground up to handle the load and torque.

I am not thrilled with hub motors, as I believe they are too vulnerable to damage and leave far too much unsprung weight at the wheel.

My inclination is to use an off road motorcycle style chain drive arrangement --- with the motor driving a sprocket as close as possible to the swing arm pivot point to limit chain length / geometry changes, or the wheel riding "up" the chain on acceleration.

Not terribly thrilled with the motor driving the standard bike derailler / crankset if the power output exceeds 700 watt (and peak loads higher).

If we assume that the standard derailler / crankset is sized to handle a maximum human output of 2,000 watt and a sustained output of maybe 300 watt (world class athlete power, not average cyclist), then even at 700 watt, the derailler is overstressed by well over 2X --- the standard design safety margin.

Then there are the special problems posed by using lead acid (heavy) battery technology, in terms of dynamic balance, etc.

All of this is leading me to think in terms of a very strong mountain bike as a minimum starting point, or a custom built frame using key components from an 80cc motocross bike.

e.g. the rear suspension arm, front forks, wheels, etc. on a custom frame that allows the batteries to be placed center (between wheels), low to the ground, etc. on a step through frame.

 

[Miles]

It's better to use torque values when discussing stress on components. Otherwise, there are too many assumptions. Take the input torque and multiply (or divide) by the transmission ratio.

Assuming you're talking about an ebike, and not a emotorcycle, the combination of pedal and motor drive at sprockets co-axial with the suspension pivot would be a good solution, as long as the ratio from there to the wheel is close to 1:1. You'd also need to set the pivot point position to minimise the effect of the rear wheel contact force.

 

[GTA1]

Update.

Today, the front side pull caliper bushing (that presses against the return spring) broke on one side.

This bike is really not built for serious use (defined as less than 10km per day).