Seized Bolt Anyone?!

[WAH]

Yes, I know, not very “technical” but beggars can’t be choosers etc.

Monster 900sie resurrection is underway, poor old thing is in a bit of a state, started taking bits off to clean / lube etc. The rear shock being very poor but has proved most unwilling to be removed, specifically the lower 10mm mounting bolt passing through the alloy swingarm and the lock nut sits in a very handy saddle washer that prevents proper attention.
Suspect galvanic corrosion maybe an issue so I had to go all out medieval with heat, cocktail of penetrating fluids, impact gun (240v 450nm) breaker bar with scaffold tube attachment and still no joy to be found. It’s the old issue of trying to decorate the hallway through the letterbox.

Before I dive into yet another rabbit hole and attempt to remove swingarm (those exhaust studs don’t look healthy!) with shock still attached, just wondered if anyone here had suffered a similar fate and successfully resolved issue.
Cheers.

[Nickj]

I once spent a frustrating few hours removing an almost inaccesible nut on a honda.
I had to use a very tiny chisel with a 5mm cutting edge to get at the nut, split it after an hours wacking.

You don't know anyone with an induction heater or an arc welder? Often really a really brutal heating is needed, you want to be seeing the offending nut go a dull cherry red.

[WAH]

Thanks Nickj, a younger me would have definitely had the burning gear to it by now!
I didn't want to get too physical with it as I don't think the alloy swingarm will take it, another issue with heating being the proximity of the Ohlins (nylon) rebound adjuster and the heatsink nature of the parent material.
Time is on my side I'm not in rush.

[spuggy]

Timely question; I was musing about the same problem - need to upgrade the shock spring on my 900Sie, and pretty sure that this lower bolt might be just as annoying as the one on my S4 that I eventually just got Moto Rapido to deal with.

Took them over a week, after everything else was done. I asked them what the trick was - they said a combination of heat, judicious use of impact (in both directions) and leaving the penetrating oil to soak between bouts.

It's my impression that many of the factory fasteners may have been assembled completely dry (as were, apparently, the headrace bearings in my 900 Dark)... So if they can be quite tedious if they're exposed and have never been disturbed.

Another favorite are those mushroom head bolts on the rear hugger that rust and look like garbage - and promptly snap off with the tiniest amount of force when you attempt to remove them...

[Mark64]

Ducati -turning riders into mechanics for nearly 100 years ;-)

[Darren69]

Cornerspeed had to deal the the bottom shock bolt on my S4 too. Neil was like thanks for that Darren!

[Mr Gazza]

I was looking at that bolt, or more specifically the nut, the other day.
I was wondering what to do if it seized. It's a compete bastard though!
My best idea would be to try a reciprocating saw of some sort and try to split the nut with that, splitting the end of the bolt at the same time obviously.

Flames would seem like a bad idea, but I wonder if it would be possible to apply some kind of induction heat to the nut and bolt only?
My first thought about how to do that would involve a stick welder, but could get dodgy!
I've seen a spanner dissolved in seconds when it shorted across a lorry's 24V batteries, so there's a thought, but could get dangerous! The spanner mentioned branded the guy's hand before he could let go of it. (He deserved it to be honest!!)
I reckon a dab on each end of the bolt with 24V jump leads would scare the life out of it!..

My bolt was out less than a couple of years ago when the shock was serviced and I'm just hoping that I applied my routine moly grease to the threads.
Might have the swinging arm out soon, so that'll be a good time to replace the bolt and nut with Ti and Moly.

Good luck with the horrible thing mate, and don't hurt yourself!

[WAH]

Thanks guys appreciate the support, it's going v slowly and I've bitten the bullet on the ultra (expensive?) penetrating fluid, if that fails then it'll be time to get creative.
There's plenty to do in the meantime, had the tank filler off and the bike has obviously stood a while on its sidestand, luckily it only had a small amount of fuel in it. I say fuel but I can't swear to it, nasty rusty brown yuck with zero odour.
Tis the bike that keeps giving.

[Nickj]

Originally Posted by WAH

I say fuel but I can't swear to it, nasty rusty brown yuck with zero odour.

The joys of ethanol

Good luck with the nut, if sublety fails brutul violence will work

[Martin Duke]

Originally Posted by WAH

Thanks Nickj, a younger me would have definitely had the burning gear to it by now!
I didn't want to get too physical with it as I don't think the alloy swingarm will take it, another issue with heating being the proximity of the Ohlins (nylon) rebound adjuster and the heatsink nature of the parent material.
Time is on my side I'm not in rush.

This could be worth looking at - AdriansModelAeroEngines.com (Technical Topics, loosening rusted nuts and bolts) - an American machinist magazine did an experiment comparing a range of penetrating fluids and found that a home brewed potion consisting of equal parts Automatic Transmission Fluid and Acetone performed much better that any commercial product. They compared the torque required to loosen a batch of corroded fixings after being treated with the different products. You could use cellulose thinners instead of acetone.

Good luck! Martin

[350TSS]

^^^ I agree, 50% Acetone and 50% diesel is also outstanding. Dosing the offending part daily for a few days usually works for me

[Darren69]

You got to be real careful with that bottom shock bolt 'cos it's captive in the swingarm. If it starts spinning you're in a world of bad.

[Mr Gazza]

On a 900Sie the bolt has to be turned several times anti-clockwise to remove it, then it comes right out and can be replaced or renewed.
The nut is stopped from turning by locating in a slot in the swinging arm which is lined with a snug fitting steel channel, fitting both the slot and nut. neither are attached to the swinging arm and fall out once the bolt is removed, so not sure how the bolt is "captive" as such?

Be careful of paintwork and other soluble parts with Acetone. It dissolves most things, some quite quickly.

Maybe time to try the rattle gun again. I find very short blasts to work best with those. The first hit is the one that does the trick in most cases. Holding the trigger relentlessly doesn't seem to achieve much!

[WAH]

^ agree with your observations, I'm getting to stage where I'm having to ration the use of the imapact gun, it's rounding off the hex and soon the bit won't fit. Still waiting for the wizards **** to arrive (Innotec) that will be the decision point on what happens next.
The swingarm removal is going to put up a fight too, the spindle bolt adjacent to the output shaft has been mangled by the chain, judging by the scars on it I'd have to guess the chain has come off it under load.
Once again thanks for all the input, it's keeping me sane.

[Mr Gazza]

Obviously good quality Allen bits help in that department, but a trick I often use is to put some coarse grinding paste in the Allen head. it helps a lot in the fight against rounding out.

A case saver is good for peace of mind. A chain break can cost an engine!
http://www.ukmonster.co.uk/monster/s...ad.php?t=49399