Author Topic: Holes in the frame??? anyone else suffered this  (Read 5883 times)

Offline ColCB400 4

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Holes in the frame??? anyone else suffered this
« on: December 11, 2014, 07:06:43 PM »
Got my frame back from the powder coaters and started building... like you do.
I noticed two holes have appeared just behind the swinging arm bolt, on the nearside both inside and out.
They are too neat to be corrosion... 5mm dia.
I think they are drain holes brazed up prior to painting during production.
I can use blanking grommits to seal them up, the location isn't structural so it shouldn't be a problem.

anybody else got annoying holes?
did the powder coater get too carried away when blasting?

Offline matthewmosse

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Re: Holes in the frame??? anyone else suffered this
« Reply #1 on: December 11, 2014, 07:46:57 PM »
I had my bike frame rot through- I don't remember what the first sighns were, I saw new holes so bashed it  with a slag hammer, and rapidly found a whole lot of rot. Not the end of the world, and I repaired it, including the begginings of structural rot.
Got a 500/4 with rust and a sidecar and loadsa bits. nice and original and been round the clock

Offline Bitsa (Ralph Wright - RIP)

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Re: Holes in the frame??? anyone else suffered this
« Reply #2 on: December 11, 2014, 07:56:23 PM »
Guys
Have heard of this but luckily not experienced it.From what I remember reading about is early ones did not have drain holes somewhere in the bottom.So later ones had neatly drilled holes for water to come out.I have built 2x 750s and one 400 and like I said not had this problem but I dare say there are lots out there that have.
Cheers
Bitsa
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Offline Clem2112

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Re: Holes in the frame??? anyone else suffered this
« Reply #3 on: December 11, 2014, 07:59:44 PM »
There are drain holes in the lower downtubes -  at the bottom , near the back as far as I can remember. Either there or in the cross tube near the  centre stand pivot.
Only reason for them was to let gases out when the frame was welded together.

Offline Green1

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Re: Holes in the frame??? anyone else suffered this
« Reply #4 on: December 11, 2014, 11:00:14 PM »
Both my k1's didn't have drain holes I pulled the gold bike onto its main stand 2 years ago and a weld broke.The frame tubes rotted inside out and are now wafer thin.(hoping to fix it this year)
I drilled to small drain holes in the frame to the green bike and was shocked how much water came out.

Mick
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Offline royhall

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Re: Holes in the frame??? anyone else suffered this
« Reply #5 on: December 12, 2014, 07:42:37 AM »
Just rebuilt my F2. When I stripped it I got a fair amount of water out of the frame, lucky that I wasn't reusing the frame as the tube holding the centre stand had rotted nearly through. During the rebuild I kept thinking "I don't think I would rush to take this bike out in the rain" as loads of areas are open to ingress of water (especially the electrics). Think I will be carefull cleaning it as well. At least it takes 35 to 40 years to rot though. At 55 I will probably have rotted through as well by then.
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