Jamis Hudson bolt sizes for rack mounting?

MikeSSS

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The Hudson is sort of a pedal forward, foot touch when you stop bike. To me it appears to be between a Townie and a conventional bike design.

I bought a used Hudson and am now trying to mount a rack for the battery. M5 .8 bolts don't seem to work, M4 is too small. Anybody know what bolt size the Hudson is drilled and tapped for?

Thanks
 
Might not be metric, but a M5-0.8 did fit into the front fork dropout, though with some difficulty.

I'll call a Jamis dealer in a few days.
 
MikeSSS said:
The Hudson is sort of a pedal forward, foot touch when you stop bike. To me it appears to be between a Townie and a conventional bike design.

I bought a used Hudson and am now trying to mount a rack for the battery. M5 .8 bolts don't seem to work, M4 is too small. Anybody know what bolt size the Hudson is drilled and tapped for?

Thanks

An M5 tap is $4 at the hardware store, in case you want to convert it to a known size, or if the threads weren't cut very well in the first place.
 
It might be thick paint in the threads, a tap would fix that.

If I knew it was M5-0.8 I'd run a tap through it. Pretty sure I have that tap size.

Anyway, I was trying to install a rack for the battery bag, but have used a seat tube clamp rack for now. A regular rack provides a place for the controller but such place is not there for the seat tube rack I'm using.

Seems like "it's always something".
 
The rear dropout has two screw holes, a top one and a lower rear one. The lower rear hole is M5-0.8, the top hole isn't, it's smaller diameter or so it seems. Perhaps that top hole is a #10 fine or course pitch.

The adventure continues.
 
Bought bolts and did trial and error, found the answer.

Lower and more rearward holes are M5x.8 pitch. The upper and more forward holes are 10x32.

10x32 screws will fit in the M5x.8 holes but are loose. M5x.8 screws are a bit too large diameter to fit in the 10x32 holes.
 
that just seems wierd.

i wonder if they intended the holes for different types or brands of accessories, whcich each commonly use different bolt sizes?
 
The holes are just messed up. Tap everything to M5 and make your life easier. I've had a couple of Jamis bikes and all the nut and bolts are metric. Extremely unlikely that they'd use US machine screw sizes on it; but pretty likely they screwed up the manufacturing by not changing their tooling when required.
 
Removed the temporary seatpost mounted rack and installed a dropout mounted rack. I used the M5x.8 holes in the rear dropouts.

Now there is room for a Thudbuster Long Travel seatpost. That's why I wanted to not use the seatpost mounted rack.

Thanks for the help.

Mike S
 
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