500W limited at 25 KM/H (16 MPH) why?

[Flyman]

Hi everybody,
I finished to integrate my GM 500W 36V
A friend of mine did the same with the same kit.
Both are running but the pb is that he manages to reach about 30 Km/H without pedaling whereas I only reach 25 Km/h.
Kits and batteries (36v 12AH) are strictly the same so I wonder what is limiting my speed.
I tested my bike with his battery but nothing changed.
Is there a component in the controller which could produce such a loss of speed?

Please help me.
I thank you in advance.

[Leslie]

Sorry for the late reply!

Im sure everyone here can help.

My guess is it might be the controller or the hub. Well there isnt a lot else.

Try pumping your tires to max and check you have on resistance on the brakes.  A warped rim can take 2 kph, tight brakes can take away another 2 kph and flatish tires can take a whopping 5 kph.  Just fine tune your bike first then see how you go.

[nitecheck]

Hi Flyman -  as 317537 as has said - only the controller or hub remain as suspects.
...20% less performance is a real problem for identical kits.

(If there are no other factors to consider -different gauge wiring off the battery pack, binding brakes, heavier bike, higher PSI &/or slim tyres.. etc)

Firstly - Try switching controllers between the bikes to see if this a controller issue (seems like the prime suspect).
If no change - check your hub's ID (on the side of the hub plate) just to ensure that you do not have a lower spec hub.

Lastly I would take the time to swap the hubs over - but use your controller.. to identify which unit is limiting performance - when you have I identified the problem - advise GM & see if they have a solution - replacement part etc.