Keeping the crank boom straight

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Keeping the crank boom straight

Postby bradwoodbr » Tue Aug 26, 2008 11:15 pm

My M5 Shockproof cranks are easily knocked out of alignment no matter how hard I tension up the two holding bolts on the underside of the boom.
Does anyone know of any after market bracket or homemade fix? I would assume the problem will only get worse with wear. Any ideas shared would be greatly appreciated.
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by BNA » Tue Aug 26, 2008 11:40 pm

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Postby Kalgrm » Tue Aug 26, 2008 11:40 pm

G'day Brad,

Welcome to the forum. I hope you have as much fun around here as I do! :)

I think this is one you're going to need to take to the makers. Fire off an email to them and ask what they recommend. I doubt you're the first to have the problem.

My ideas involved Loctite or teflon tape ...

Cheers,
Graeme
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Postby bradwoodbr » Wed Aug 27, 2008 6:11 pm

Thanks Graeme, It is a very in formative forum. I have been reading posts for a week or so.
FYI - The supplier has suggest the following:
1. Remove bolts and regrease so you can fully tighten them.

2. If that doesn't work you can roughen up the inner tubes a bit with some fine grit to help the outer tube "bite" / hold it.

I will give this a try and let you know. Perhaps your tape idea would be better than roughing up the inner tubes.

Will let you know.

By the way have you ever ridden a medium to low racer?
If you have what did you notices as the big advantages with your Bachetta. I am thinking of upgrading and don't know which way to go yet.

Cheers
Brad
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Postby Kalgrm » Wed Aug 27, 2008 8:02 pm

G'day Brad,

No, the only 'bent I've spent any time on is my Bacchetta.

Maybe next time we ride together we can swap bikes for a while (swapping pedals too.) Of course, let's not do this on an Audax ride! :)

Cheers,
Graeme
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Postby Uba Tracker » Wed Aug 27, 2008 8:07 pm

G'day Brad, if you find that you're still having difficulty securing the boom after applying the other recommendations, it might be that you just need a bit more clamping pressure. These hydraulic hose clamps work a treat Image and in reality don't look all that bad, well OK they look better than a daggy old muffler clamp. These suckers have got some bite too AND they're available in stainless steel so no worries about it rusting away. Enzed or Pirtek will be able to help you out. This particular unit is a Mikalor Supra but there'd a hundred others just like it under another name. Good luck :D

regards

Harry
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Postby Kalgrm » Wed Aug 27, 2008 8:14 pm

bradwoodbr wrote:By the way have you ever ridden a medium to low racer?
If you have what did you notices as the big advantages with your Bachetta. I am thinking of upgrading and don't know which way to go yet.

Cheers
Brad

A bit more on this - I think you should start a thread for this question. There are a few people here who could offer opinions on why they chose what they did.

Just be sure to let us know what you're unhappy about with your current bike and what area you'd like to see an improvement in.

Cheers,
Graeme
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Postby bradwoodbr » Thu Aug 28, 2008 12:30 pm

Hi Graeme and Harry,
Thanks for your ideas and comments. Harry I will definitely get one of those stainless steel clamps and give it a try.
Graeme, your idea of swaping bikes on a ride is a good one. We are about the same height, so fitting would be fine. Let's do this soon. Will contact you out of forum.

Cheers
Brad
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Postby Storm » Thu Aug 28, 2008 9:56 pm

Wrap some electrical tape around the frame before you use the clamp to avoid scratching the paint.
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Postby william » Sun Aug 31, 2008 4:58 pm

Hi Brad,

From a fitting point of view regarding your clamping boom I find it strange the fit is less than stellar. Without looking at it things that crossed my mind were the screws bottoming out or threads not cut deep enough into the frame screw housings. I'm assuming also there is a slot cut along the underside of the boom housing too. Sometimes a lubricant is used to prevent corrosion, this is a mistake on clamping surfaces such as this and should be spotless. If anything, something like WD40 wiped on, and then vigourously cleaned off with a soft cloth will do. Do not rough it up with anything, a clamped smooth surface will have greater friction resistance.
Also check that the boom and housing are actually round. There is a lot of torsional force placed in the front boom and distortion can happen from a strong rider or a possible mishap.
Hope you find the problem then you'll have the solution.

Regards,

William.
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Postby bradwoodbr » Mon Sep 01, 2008 12:34 pm

Hi William and Others,
Thanks for all your ideas and advice. I will take photo of the clamp and show you what it is like.
Brad
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