Stuck triple clamp pinch bolts

[400_racer]

Im having some major problems with what i guess is galvanic corrosion(?) on the triple clamp pinch bolts. I have free'd all off bar 3 i think.

The worst being the RHS, lower, middle bolt, which the previous owner has obviously had a go at and sheered the head off - and promptly glued the head back in place to make it look like nothings happened. Unbelievable.

I have drilled and tried easy outs. Soaked in penetrating spray. Heated the triple clamp. Hitting and shocking whats left of the bolt. Ended up drilling right through the middle of the bolt to try and relieve it. Repeated the above, but nothing. Went next size up easy out, still nothing. Unfotunately, my drilling is slightly off centre, so cannot go much bigger without damaging the ally clamp.

Havent checked yet, but with the top and bottom bolt removed, i think theres just enough space to get a hacksaw blade, i thought i could chop the offending bolt in two, meaning each bit is held in place with corrosion, so hopefully each half may come out. What do you reckon?

The other two stuck bolts with the heads intact i may try heating/easyouts etc route.

Any ideas guys? Anyone know of any solution that will neutralise the ally/steel corrosion? I read somewhere that diluted battery acid will dissolve the ferrous component of the corrosion if left to soak. What would you do... Other than taking the b*astard thing back to the previous owner of course

Thanks,
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[wasp4banger]

I'd be tempted to drill it out and put a helicoil in.

http://www.amazon.co.uk/Silverline-...P9OW/ref=sr_1_1?ie=UTF8&qid=1343993159&sr=8-1

I put copperslip on mine to prevent them seizing, use this on every dissimilar metal bolt assembly I put together.

 

[pscook]

As you have it drilled down the center, try zapping it from the other side with the next size larger drill bit. I know you don't have much room left, but you might get away with one fraction larger. Running a bit from the back side might help thread it out in the proper direction. You should be able to remove enough stuff to get the clamps off the bike and to a machinist, barring success from other attempts.

And, worst case, toss in a heli coil if you bugger the threads.

 

[Fred1956]

Another thing to consider as the center bolt is a redundant fastener, just get it out of there and don't worry about replacing it. Many thread posts about 'just barely tightening' or leaving the center bolt out altogether

 

[Eric]

Another thing to consider as the center bolt is a redundant fastener, just get it out of there and don't worry about replacing it. Many thread posts about 'just barely tightening' or leaving the center bolt out altogether

I'd do this if it was my bike.
As for the other 3 stuck bolts, what penetrating oil are you using ? I've had the best luck with sea foam deep creep its way better than wd40 and heat the triple clamp before you even try to turn them out.

 

[400_racer]

Thanks for the replies guys, had another go this afternoon with some success!

All bar one of the top 4 bolts were stuck, RHS bottom and LHS both. The allen heads on all pretty much shot. Started on the RHS bottom one and really screwed the head up, so started drilling that to fit a much larger extractor. Was going well when all of a sudden and v.loud crack made me sh*t myself thinking id busted the clamp somehow. But it was just the head of the bolt sheered off, few! So started from the back of the bolt (nice and central!), and low and behold, just after moving up to the next size drill, it started moving Carried on and fitted the extractor and out it came from the back nice and easy!

Will have a go with the 2 LHS ones tomorrow, theyve been left to soak in Halfords penetrating oil over night, so fingers crossed they behave themselves too.

Regarding the lower middle bolt. Unfortunately due to the clamp web design, you cannot get a drill through to the back of the bolt. So, like you say Eric and Fred, i will leave as is and try running with just the two bolts. The fork is now free so can now be removed.

The way the bolts are, i dare say they have never been out - makes you wonder what state the fork oil etc is in I guess i'll find out soon enough...hopefully

 

[Jakobi]

Heat and impact are your friend too. Hanging off a bar applying steady force will either round the heads out or break the bolt.

 

[gasmonkey]

Let sleeping dogs lie.Those center lower bolts are not needed.

 

[400_racer]

Well I got the bolts out with no more breakages, combinations of plenty of heat, penetrating oil, impacts, and managing to force an oversized star socket into the already half rounded off bolt heads for better purchase did the trick

So....I have the forks out and did an oil change, the stuff which come out looked pretty grey and murky.

Just been having a read of older threads and am I right in saying its normal that there should be little noticable difference in extremes of damping rates when pushing on the forks on the garage floor? I mean going from clickers all the way in, to all out.

The reason being the forks aren't moving at high enough velocity for clickers to make an obvious difference, and due to the high amounts of free bleed on the Zone 45's? I.e it will be noticable on the bike.

Sorry if this has been asked before, just seemed a little odd to me.

Thanks again

 

[andoman]

When drilling out a broken fastener, a left-hand drill bit is the ticket. The heat generated by the drilling and the left hand action will often back the fastener out with out the need for the easy out.