Woosh Gran Camino seat post cap bolt.

[Fleabag]

Hello,

I have had and been using my Gran Camino for about a year and a half I was generally really pleased with it, though the thumb throttle stopped working pretty early on - I not sure what's wrong with it but I rarely used it so haven't looked into it.

I've managed to break the seat post cap bolt twice not sure how as I weigh about 14st max and it says suitable up to (20st) 25st on tarmac roads (which is where I broke mine). I took the broken bolt to a couple of bike shops and toolers but they said they have nothing equivelant as it seems to be a non standard size (chinese sizing?). I Messaged the maintenance guy at Woosh the first time and he was very good, after sending me the wrong bolt initially he sent me a replacement. This second time he seems to be ignoring my emails for some reason - I'm not asking him to send me a replacement - just tell me the spec or where I can source it as I'll probably get a few or get a titanium version if possible.

It's a bit of a shame as had only good things to say about Woosh and was going to get a Rambletta as my next bike soon but this has put me off a bit as my bike is currently unrideable and it's proving to be a bit frustrating.

Can anyone help me with the bolt - the biggere silver one is incorrect (7mm?) its the smaller black one I'm after. Thanks
View attachment IMG_20230807_170923.jpg

 

[saneagle]

Hello,

I have had and been using my Gran Camino for about a year and a half I was generally really pleased with it, though the thumb throttle stopped working pretty early on - I not sure what's wrong with it but I rarely used it so haven't looked into it.

I've managed to break the seat post cap bolt twice not sure how as I weigh about 14st max and it says suitable up to (20st) 25st on tarmac roads (which is where I broke mine). I took the broken bolt to a couple of bike shops and toolers but they said they have nothing equivelant as it seems to be a non standard size (chinese sizing?). I Messaged the maintenance guy at Woosh the first time and he was very good, after sending me the wrong bolt initially he sent me a replacement. This second time he seems to be ignoring my emails for some reason - I'm not asking him to send me a replacement - just tell me the spec or where I can source it as I'll probably get a few or get a titanium version if possible.

It's a bit of a shame as had only good things to say about Woosh and was going to get a Rambletta as my next bike soon but this has put me off a bit as my bike is currently unrideable and it's proving to be a bit frustrating.

Can anyone help me with the bolt - the biggere silver one is incorrect (7mm?) its the smaller black one I'm after. Thanks
View attachment 62006

It looks like a standard M6 cap screw to me that you can buy in Screw fix. The only important thing is to get one long enough. Longer is OK. If you get one with the plain shoulder, the shoulder length needs to be the same or shorter. A zinc plated or black japaned one won't break as easily as the stainless or high tensile ones do.

M6 Cap Screw 50mm Zinc Plated for sale | eBay

Find great deals on eBay for M6 Cap Screw 50mm Zinc Plated. Shop with confidence.

www.ebay.co.uk

 

[Fleabag]

Thanks for the reply, Saneagle.
Unfortunately I bought a couple of M6 screws and they are slighty too thin, whereas the 7mm are too thick. it seems to be somewhere between the 2 though the correct bolt seems to be much closer to 7mm than 6mm (in the photo the silver bolt is 7mm)

 

[matthewslack]

Probably 1/4 inch then: 6.35mm.

Did the first one fail in the same place?

 

[matthewslack]

Too big! M64 really does mean 64mm, not 6.4mm.

 

[saneagle]

Thanks for the reply, Saneagle.
Unfortunately I bought a couple of M6 screws and they are slighty too thin, whereas the 7mm are too thick. it seems to be somewhere between the 2 though the correct bolt seems to be much closer to 7mm than 6mm (in the photo the silver bolt is 7mm)

I've seen 100s of those clamps. They're all M6. Nobody ever uses 7mm on a standard part. You have to go back to the 1960s to find equipment with 1/4" threads, so that's not likely either.

Measure the diameter of the shank and tell us what it is. If you don't have a caliper gauge, cut a slot in some cardboard the exact zize, then measure the slot with a ruler.

 

[matthewslack]

My American bike trailer components are littered with 1/4" bolts. Alive and well across the pond.

 

[saneagle]

My American bike trailer components are littered with 1/4" bolts. Alive and well across the pond.

Did OP buy his bike from a USA manufacturer then or was it a Woosh bike from China?

 

[saneagle]

Why not buy a new clamp? They're not exactly expensive.

Seatpost Clamp for sale | eBay

Find great deals on eBay for Seatpost Clamp. Shop with confidence.

www.ebay.co.uk

 

[Raboa]

Fastener Sizes in Inches
Metric & Inch Size	Diameter (inches)	Rounded to Nearest 64th (inches)
M6	0.2362	15/64
1/4	0.2500	1/4
M7	0.2756	9/32

 

[Raboa]

Google Search

 

[egroover]

should be a measurement value stamped on the existing clamp, if it's 34.9 here's a brand new seat clamp with bolt for a smidge over £3

 

[matthewslack]

Clean version of link:

https://www.amazon.co.uk/VGEBY1-Bicycle-Aluminum-Mountain-Cycling/dp/B07S7T7YKP

All the rest is people up to no good!

 

[egroover]

Clean version of link:

https://www.amazon.co.uk/VGEBY1-Bicycle-Aluminum-Mountain-Cycling/dp/B07S7T7YKP

All the rest is people up to no good!

i think my link contained search criteria, dunno whats 'up to no good' lol, have deleted it now in case it linked to my account or something lol

 

[matthewslack]

i think my link contained search criteria, dunno whats 'up to no good' lol, have deleted it now in case it linked to my account or something lol

Impossible to know what all the rest is doing!

 

[Woosh]

Can anyone help me with the bolt - the biggere silver one is incorrect (7mm?) its the smaller black one I'm after. Thanks

It's a standard seat post clamp. Please email support@wooshbikes.co.uk so I can r

Hello,

I have had and been using my Gran Camino for about a year and a half I was generally really pleased with it, though the thumb throttle stopped working pretty early on - I not sure what's wrong with it but I rarely used it so haven't looked into it.

I've managed to break the seat post cap bolt twice not sure how as I weigh about 14st max and it says suitable up to (20st) 25st on tarmac roads (which is where I broke mine). I took the broken bolt to a couple of bike shops and toolers but they said they have nothing equivelant as it seems to be a non standard size (chinese sizing?). I Messaged the maintenance guy at Woosh the first time and he was very good, after sending me the wrong bolt initially he sent me a replacement. This second time he seems to be ignoring my emails for some reason - I'm not asking him to send me a replacement - just tell me the spec or where I can source it as I'll probably get a few or get a titanium version if possible.

It's a bit of a shame as had only good things to say about Woosh and was going to get a Rambletta as my next bike soon but this has put me off a bit as my bike is currently unrideable and it's proving to be a bit frustrating.

Can anyone help me with the bolt - the biggere silver one is incorrect (7mm?) its the smaller black one I'm after. Thanks

Could you please email support@wooshbikes.co.uk? Woosh not Whoosh.
The seat post clamp is standard part, you can get it at Halfords, amazon or ebay. I'll send you the right link.

 

[matthewslack]

Probably 1/4 inch then: 6.35mm.

Did the first one fail in the same place?

@Fleabag, if they always fail in the same place, and a failure during riding could be a problem, then just replace regularly before failure.

In the threaded section, especially first thread, is a major change in cross section and so a stress concentration where a fatigue crack might start.