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Can I make a distinction here between 'springing' open the frame wider by an extra 5mm to fit a wider hub, and 'spreading' or permanently cold setting/spreading the chain stays wider. I have on occasions fitted wider 135 mm hubs on to 130mm wide chainstays by springing them apart, although it...

I am glad to see your brakes are performing well. I think one of the reasons your brakes work so well is because the pads are parallel to the rims and move horizontally and accurately towards the rim, ensuring even wear on both the pads and rim. I have replaced many worn out rims with ordinary...

Thank for that information. I also had very bad luck with a pair of ordinary Land Cruisers 700 X 42 with frequent punctures. Even very small thorns seem to puncture. I eventually took them off as I thought someone had put a curse on them. They were only slightly worn. They were a nice grippy...

Thanks. The one thing I do notice is that there has been some additional restrictions listed in the 2017/2023 document index that are not in the 2009 documents. For example, there appears to be an extra section 4.2.17 'Anti-Tampering Measures' which makes me wonder precisely what these measures are?

I came across an abridged amended copy of EN15194 (Nov 23) which at least clarifies the position for me and that I can now show on paper. The position seems to be more or less what Flecc and saneagle are saying. ( I think). The paper defines On page 10 it states (my emphasis above in bold)...

I wonder would a carbon frame survive the 100 foot drop in video below.

Thanks for reply. I have heard stories of air getting into the brakes and having to bleed brakes after bikes being upside down which puts me off upgrading to hydraulic brakes. Is this a regular or a rare occurrence?

I always turn the bike upside down to repair punctures. But I have mechanical disc brakes. Has anyone ever had any issue/problems with doing this with hydraulic brakes?

I think its the other way around. A motor running at its rated value of 250W will be close to its specified maximum temperature or for the temperature class it falls into( if this is applicable). If its running cool at 250W its over rated capable of more. Ideally for the test, it should run...

I'm not sure if that's the case. If you read the report, what the examiner has passed is that 'The maximum continuous rated power: 250W' It is possible that the same motor would pass say a separate 350W (or possibly more) test for a different market/juristriction/speed limit under a different...

I found a copy of a recent ebike 50 page EN15194 test report. The relevant section of the report on power is as below. The engineer/tester just fills in the letter 'P' (for pass).

The second alternative test proposed is different than the first test. The first test only rates the bare motor at the shaft and is a thermal test. The second test is not a thermal test and tests the whole bike along with its controller, battery etc. It estimates the power by calculating the...

I specifically said above that 'You need to take the chain off the bike'. This solves that problem.

By the way, there was a way proposed that could test and rate the output power without a lab or any special equipment. I dont think it will work with a torque sensor but will certainly work with a hub motor. You need to take the chain off the bike and fit a pannier rack as you need to add...

But I think this is no different than say with a motor car. The engine power/cc/bhp/emission rates is what the document or label on the engine says. Most people buy cars and never question the rating. We leave the rating and certification to the civil servants and the car manufacturers to worry...

PS If you think about it, it seems from above that it may not be too difficult for say a 36V motor with a 14 amp controller to pass the test. Although the electrical input may be 500w, if the test is done at say a slow cadence or say the 55 -60% area on the efficiency curve, then the actual...

I think the test its simple enough as far as I can see.. I would think the motor is loaded with a 250W mechanical brake + 15% allowance for errors etc and ran until temperature equilibrium is reached as explained in document below. The actual max temperature is supplied from the manufacturer...

Below is what I reckon although I am sure you will get other opinions. I think the same motor can have different power ratings depending on its application as specified by the manufacturer e.g. A motor thats tested and rated to 250w continuous mechanical output at 25Km/hr could also be tested...

Different ways to activately balance a battery without load resistors. One way is for the BMS to charge a capacitor with the high cell and discharge it back into low cell. etc. Exemplary passive (left) and active (right) balancing circuit topologies

Just a tip that might help. If any of the spokes get scratched, you can use black touch up paint or even cheap black nail varnish .