having had a similar experience recently with a different seller on here than this thread sadly documents I'm getting a fair idea about the part of this forum that is about marketing parading as an interest in pedelecs, one lives and one learns..
Bosch bearings
- Thread starter Artstu
- Start date
Did you remove the bearing to measure the i/d or just measure the fag shaft diameter?
Most bearings have a tapered edge on the i/d and o/d to feed the bearing onto the shaft - can you see the taper?
My reason for asking this is because I have found this:
http://machinedesign.com/recreation/electric-bike-balances-pedal-and-motor-torque
Maybe the shaft is assembled so the bearing is removed in the opposite direction and sits against a lip as shown on the other end of the shaft. If it does then I suspect it is a standard 6004 size.
Most bearings have a tapered edge on the i/d and o/d to feed the bearing onto the shaft - can you see the taper?
My reason for asking this is because I have found this:
http://machinedesign.com/recreation/electric-bike-balances-pedal-and-motor-torque
Maybe the shaft is assembled so the bearing is removed in the opposite direction and sits against a lip as shown on the other end of the shaft. If it does then I suspect it is a standard 6004 size.
I've read all of this sorry tale including your bobbing and weaving, and the way you've backtracked of what seemed like solid promises of help.
I don't jump to conclusions very readily but one definite conclusion I've come to after this is to never in a million years buy a Bosch motored bike, and to give KTM a wide berth too.
I've had the bearing off. and 21.2 is in the right ball-park, I have a cheap digital vernier that is flashing on and off even with a new battery.
I'll just add that the bearing place I went to first, was convinced a 20 mm bearing would fit, it was miles off, he then sent me a 22 mm bearing, that didn't even have the right outer diameter, obviously that was loose.
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All I can find is probably your contact for a 21.4mm version.
http://translate.googleusercontent.com/translate_c?depth=1&hl=en&prev=/search?q=6004-2rs-21.4&biw=1280&bih=643&rurl=translate.google.co.uk&sl=zh-CN&u=http://detail.1688.com/offer/506423402.html&usg=ALkJrhjp41wPVzU2SxXCO_MVYHtg5FzYXg
Another Company link - they appear to deal in non standard types with a smaller MOQ - might be worth an email.
http://ldbcl59.21bearing.com/product/48201/scooter-bearing-6205-1-quot-2RS-C3-bearing.html
or
http://www.findbearing.com/product/industrial-bearing/deep-groove-ball-bearing/inch-deep-groove-ball-bearing/6004-21-4-bearing/
Cheers. I'd like to think that someone else can come on and confirm the bearing/shaft size. The input from shops that sell and stock Bosch motors has been notable by its absence.
The shaft should be measurable on the non drive side by the alloy spacer bush, as the shaft protrudes from the housing.
The shaft should be measurable on the non drive side by the alloy spacer bush, as the shaft protrudes from the housing.
The user should not have to use engineering skills and a micrometer to obtain a spare part.
The bearing should be available as a part number from Bosch.
Warranty or not is irrelevant, although in this case I would expect to pay for the part.
But in return, I would expect the part to readily available, which it clearly is not.
The bearing should be available as a part number from Bosch.
Warranty or not is irrelevant, although in this case I would expect to pay for the part.
But in return, I would expect the part to readily available, which it clearly is not.
Have Bosch actually stated that they will not supply their dealers or customers spare internal parts?
If so, makes the future value of these cycles pretty worthless as they start to wear.
Nobody is going to buy a high mileage one without reasonably priced and off the shelf spares.
In fairness that hasn't been the case with the Panasonic units which have never had any official internal spares available. Bikes using those have always sold ok second hand despite replacement units costing circa £500 plus fitting, the Giant Lafree series especially getting premium s/h prices.
However, that fact that these have been generally very reliable is a factor, and that the bearings are standard and available might have helped, had the equivalent one ever failed.
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Flecc
Time will tell but if crank drive pedelecs are to move forward volume wise they need to be seen to be an economic solution somewhere between a regular cycle and a car or public transport.
If parts are not readily available and I see no reson why they should not be then it is those who have £500 to gamble that will purchase used machines. Those who are a bit skint will think twice.
Time will tell but if crank drive pedelecs are to move forward volume wise they need to be seen to be an economic solution somewhere between a regular cycle and a car or public transport.
If parts are not readily available and I see no reson why they should not be then it is those who have £500 to gamble that will purchase used machines. Those who are a bit skint will think twice.
TBH, those who've bought second hand Panasonic crank unit bikes usually haven't even known the spares situation.
I think Panasonic's decision to design as a sealed for life unit is realisation that most bike dealers simply aren't able to deal with such repairs, especially on the electronic side, and I think it sensible if the reliability is assured.
They nearly got it right on the first series since it was generally reliable, the four known possible internal faults being rare. The second unit dealt with those and internal failures are almost unknown after nearly 7 years on the market. I've only learnt of two out of the many thousands of units sold and fitted to over 20 makes of e-bike. Their batteries have set the standard for the whole market, lasting through five years being not unusual, and the second series chargers have been unfailingly reliable.
It's in this that Bosch appear to have fallen short, quickly suffering a succession of silly problems, including excessive chain wear, left-hand crank coming loose, ingress of dirt and water and now bearings. Not a huge list, but occurring far too soon in life. Hopefully their quick introduction of the second version proves to be successful in avoiding this again.
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If the bearings are anticipated by the manufacturer to last little longer than the warranty period can we have a simple statement of :
1. Where the replacement bearings can be obtained.
2. How much they will cost.
This informtion seems something I would expect KTM as a supplier to be able to give.
1. Where the replacement bearings can be obtained.
2. How much they will cost.
This informtion seems something I would expect KTM as a supplier to be able to give.
If the thing is sealed for life, why then do we not get a lifetime warranty?
No spare parts is unacceptable to me. Maybe I still have a problem with this so called Green throw it away society.
But you don't get that on a cars either, sealed automatic boxes which clearly can be serviced are often described by the manufacturer as a 'lifetime' component.
Wether you think its acceptable or not you go back to BMW, Audi, Ford, Vauxhall with a failed gearbox they'll look to replace it with a complete new one. What we need is specialists who can rebuiled these motors...
Tell me about it, my vauxhall of less than 40000 miles has been sat for 10 months with a wrecked gearbox due to a premature bearing failure. The quote, 2k for another box.
Well the car can sit there for another 10 months, I'm using my Bosch powered ebike instead.
SRS it happens in the most high end of cars, both my RS4 and RS6 had issues with suspension, air cooler intake and gearbox failure air due to the silliest of parts exploding or leaking.
My point is that as the ebike industry grows the number of failures on certain components will rise. If bought from a dealer the motor would have been replaced, thats not the case here and I understand that. What we need is a few Bosch, Panasonic, Bionx 'whatever' specialists who are prepared to work on these failures around the country.
My point is that as the ebike industry grows the number of failures on certain components will rise. If bought from a dealer the motor would have been replaced, thats not the case here and I understand that. What we need is a few Bosch, Panasonic, Bionx 'whatever' specialists who are prepared to work on these failures around the country.
You are right, a few local ish specialists. I guess given time they may spring up around the country. Lets hope so.
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