Bike Modification

[D Rock 45]

After pulling the thread out on my bike frame two times. I desided to fix it a different way instead of rethreading again. So i drilled straight through my frame were the four bolt would of screwed into. Used a M5 drill bit to make the holes. Then bort M5 x 90mm hex cap bolts to go right the way throught, also M5 nyloc nuts to stop things coming loose .It holds on my brake booster an brake exstremly well no problems what so ever from this modification .

Thort id show you all to see what you think of it.

Thanks Dieter

[Luke Rainbird]

Next time, consider helicoiling. Great effort though

Here's hoping the frame doesn't crack too soon...

[Little Yoshi]

There is also another way. You drill the hole out to 7mm and tap it. Put in a bolt all the way in to the bottom of the frame. Mark the top of the bolt where it meets the frame and cut it off. Then drill a 4mm and tap the out to 5mm. Use the 5mm bolt to tighting up the 8mm bolt into the frame with some loctite on it to hold it in place. Leave to dry over night. And there you go. Basicaly the same but a wee bit more fiddly but more neat to.

[Balls Deep trials team]

thats gonna crack soon ....

[King C]

You'll end up crushing the tube if your not careful

[D Rock 45]

I dont see how it can crack . Its not like am not putting any exstra force on it

[Balls Deep trials team]

I dont see how it can crack . Its not like am not putting any exstra force on it

frame flex when you pull the magura lever in even know u run a booster it will still have some flex and over time it will crack

[Luke Rainbird]

You've put a hole in a tube right where there's a lot of force going through it. This creates a stress riser concentrated at that point, though it won't be quite so bad if the hole is well finished. Your brake may be mounted more solidly, but the seatstay is now weaker than it was before.

[D Rock 45]

You'll end up crushing the tube if your not careful

ive put some spacers on them to try an stop it a littel bit. an dont over do it when am nipping them up

[D Rock 45]

You've put a hole in a tube right where there's a lot of force going through it. This creates a stress riser concentrated at that point, though it won't be quite so bad if the hole is well finished. Your brake may be mounted more solidly, but the seatstay is now weaker than it was before.

ive made a clean job of it , snug fit where the bolts go, they have threaded them self where ive drill through on the bottom . so would you say it was a bad idear doing this mod ?

[Ben John - Hynes]

Yes. And it's not a mod, it's a bodge.

[Balls Deep trials team]

ive made a clean job of it , snug fit where the bolts go, they have threaded them self where ive drill through on the bottom . so would you say it was a bad idear doing this mod ?

just dont do it on a more expensive frame but good idea

[D Rock 45]

Yes. And it's not a mod, it's a bodge.

ok fair enought . i had to learn from trail an error some where ,

Edited November 25, 2010 by D Rock 45

[Ben John - Hynes]

You never know, it may last ages and prove to be really effective. Trial and error, as you suggested. Is it a real pig to set the brake up?

[D Rock 45]

just dont do it on a more expensive frame but good idea

thanks . an by some of the replys am getting it looks like i will be geting a new frame soon

[Balls Deep trials team]

thanks . an by some of the replys am getting it looks like i will be geting a new frame soon

i like how you have taken in advice well from everyone have a validation vote

[D Rock 45]

You never know, it may last ages and prove to be really effective. Trial and error, as you suggested. Is it a real pig to set the brake up?

i hope so . an ye i agreey on the setting the back brakes up . ive set them up an all seems to be fine nice an square to the rim

Edited November 25, 2010 by D Rock 45

[D Rock 45]

Thanks Balls Deep trials team

[6ft-midget]

Never mind.

Edited November 25, 2010 by 6ft-midget

[Balls Deep trials team]

Never mind.

...

Edited November 25, 2010 by Balls Deep trials team

[eskimo]

Despite what people have said, it's kinda traditional way to do it. I can't see cracking that quickly. Just don't let the nuts crash the frame.

[forteh]

Its a perfectly acceptable method of clamping the brakes, a helicoil would have been better but theres no reason why it wont work; I would have preferred to see a spreader plate on the underside of the tube though (a section of tube with the ID the same as the OD of the seatstay, cut along the length and drilled). Ive found that brake clamps dont need to be done up that tight, certainly not tight enough to crush the tubes.

You have created a stress riser in the seatstays though, cant say it will crack and cant say it wont, only time and use will tell

[Revolver]

God knows how you can strip a good four bolt mount like that.

I do mine up b*****d tight and I don't strip them.

[chris4stars]

as someone mentioned, a little plate on the underside would reduce the chances of a break....just to spread out the 'clamping' force of the nuts on the frame....the force would be reduced at least 10 fold

able to get hold of a small section of half pipe? a hacksaw and a hammer/vice and youre sorted

[D Rock 45]

Its a perfectly acceptable method of clamping the brakes, a helicoil would have been better but theres no reason why it wont work; I would have preferred to see a spreader plate on the underside of the tube though (a section of tube with the ID the same as the OD of the seatstay, cut along the length and drilled). Ive found that brake clamps dont need to be done up that tight, certainly not tight enough to crush the tubes.

You have created a stress riser in the seatstays though, cant say it will crack and cant say it wont, only time and use will tell

as someone mentioned, a little plate on the underside would reduce the chances of a break....just to spread out the 'clamping' force of the nuts on the frame....the force would be reduced at least 10 fold

able to get hold of a small section of half pipe? a hacksaw and a hammer/vice and youre sorted

i will look in to getting these plates make up in college at they do sheet metal work an will be much easyer to make than me attempting to cut a pipe in half

Thanks for all the advice an comments