Pro Connect - Loose motor bolts after 500 miles.

[TomB]

Not sure if anyone else has clocked this many miles yet but I had to tighten the three main bolts that attach the motor unit to the frame today. They had become very loose - the whole motor unit was rocking in the frame with about 3mm of play.

Riding for prolonged periods like this would easily do some serious damage to the frame.

Just thought I would mention it so others could check.

 

[flecc]

Thanks Tom, first time I've ever heard of that with a Panasonic unit. I wonder if there is any connection with the fact that it's a lightweight frame, since previous models using the unit have been rather heavier designs.
.

 

[JamesC]

Not sure if anyone else has clocked this many miles yet but I had to tighten the three main bolts that attach the motor unit to the frame today. They had become very loose - the whole motor unit was rocking in the frame with about 3mm of play.

Riding for prolonged periods like this would easily do some serious damage to the frame.

Just thought I would mention it so others could check.

Thanks Tom - I will check them.

The other bolt for people to check is the single pivot bolt that secures the chain tensioner (with spring around the outside) through the Panasonic casing. This is secured into a steel nut, fitted into a hexagon hole in the alloy casing.

Mine was very loose after 100 miles, even though the bolt had clearly been prepared with a threadlock liquid, so probably never done up tightly.

Note also that there might be a washer, used as a spacer on this bolt, to align the little chainwheel with the chain circuit. On another thread that deals with panasonic motor drag, a misaligned chain between the motor sprocket and tensioner sprocket could cause extra drag.

James

 

[TomB]

I've ever heard of that with a Panasonic unit. I wonder if there is any connection with the fact that it's a lightweight frame
.

cheers flecc.

think it's a combination of bolts not tightened when the drive unit was fastened to the frame at the bike assembly factory; and the fact that with my flat bars, bar ends, spd pedals and big cycling legs - i put quite a lot of stress on the crank assembly by delivering quite a bit of power - especially when "attacking" hills out of the saddle. i.e. i guess i'm not riding it like the average "japanese granny" .

will be interesting to see how long the nexus hub lasts - i rarely have it out of gear 8!

 

[flecc]

cheers flecc.

i put quite a lot of stress on the crank assembly by delivering quite a bit of power - especially when "attacking" hills out of the saddle. i.e. i guess i'm not riding it like the average "japanese granny" .

will be interesting to see how long the nexus hub lasts - i rarely have it out of gear 8!

Probably bolts not tightened enough initially then Tom. I often used to be out of the saddle on my Lafree, especially when load towing uphill, but the bolts never loosened.

Your hub will probably be quite safe while it stays in 8th, in my experience most hub gear failures come from clumsy changes chipping internal parts, the metal flakes them getting where they shouldn't with inevitable results.
.