Hi all,
I have a completely seized hex socket bolt where the Swingarm attaches to double conrod.
No amount of brute force and ignorance will get it to shift.
Any ideas? Has anyone else experienced similiar?
Item 9 on the below
Has the but (11) come undone?
Yep, that was the easy part!
Ok so in that case the bolt is rusted to the steel bearing inner (4) . You cant get heat to it because of the alloy ādouble conrodā so it needs pressure. You may be able to rig something up using an enormous gear puller or if not take the swing arm off and get the bolt pushed through.
Applying a thin lubricant like plus gas will help as soon as it starts moving but the rust crystals have to break before that happens.
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Thank you, the double conrod appears to move freely with the small space it has, so I donāt think itās seized in there.
Swingarm is off, I think the bolt is seized inside one or both of the Swingarm lugs.
Applied heat to the bolt but no luck.
well if it is seized in the lug that is lucky as you can apply heat cycles and plus gas directly.
I would be looking to apply constant pressure combined with shock blows so if you could set it up under a press or in a massive vice?
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Itās almost certainly corroded in solid. First off, soak it in penetrating oil - not WD40 because thatās simply a water dispersant formula. Something like GT85 or (most preferable if you can get hold of it) Kroil. Do this for a few days to allow the penetrating oil to creep through the corroded areas as much as possible. Now get a lot of heat into both lugs - two paintsripper guns will be a great help, one for each side. Try and work the bolt backwards and forwards. If it starts to move, move it back the other way to the original position and soak it in penetrating oil again. Soak, heat and repeat. If thatās a stainless steel bolt then you are going to need a lot of patience with it because thereās a chance it will be corrosion-welded to the swingarm.
At the worst, you may need to take it to a machine shop to have it pressed out.
Once itās out, youāll also need to consider the following. Thereās a possibility that the corrosion will have increased the diameter of the bolt tunnel. Simply putting a new bolt in will cause additional wear because itās now too small for the original dimensions. If this proves to be the case, get the same machine shop to open up the bolt tunnel to the next size and increase the size of the countersink to take the next size up bolt. To me that looks like an M10 or M12 bolt, so thereās enough ally in those cast lugs to take the oversize bolt. Again, the same machine shop should be able to confirm/deny this.
Iāve not had the problem on a Guzzi, but Iāve certainly fought similar setups on certain Suzukisā¦
[Edit] In case anyoneās wondering why I say āIf it starts to move, move it back the other way to the original position and soak it in penetrating oil againā, itās because when the bolt moves you will start a buildup of corrosion products in the direction of movement. If you carry on, you stand a change of jamming the bolt in harder. Moving it back puts it into a position of fewer corrosion products and allows the penetrating oil access into the areas youāve just cleared.
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Thank you! I will persevere!
Ditto- plenty of penetrating oil, sharp blows from either side, patience and time. If necessary, drill a large hole part way down the bolt in order to reduce the bolt to a thin walled sleeve, then knock it out
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I was also contemplating getting my metal hand saw either side of the double conrod to cut through the bolt. This would leave me with a section of bolt in each lug which may be easier to apply heat and penetrating oil to.
I donāt have a hydraulic press, but a do have an extra large vice
When i did mine the total cost of all 7 needle bearings (5), the 4 ground inner bearing sleeves (4,7 & 8) and the 8 bearing seals (5) was more than the Ā£550 for a new double conrod and the wishbone (14) - before i added a cost for pressing the bearings out and in.
So if the costs are still similar i think you may do well to saw down the sides of the couble conrod. I would use a junionr hacksaw to minimise metal loss - try not to take any metal off the swing arm although if you do that could be taken up with shim washers.
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Ouch!!! Will try the hacksaw method, will report back here
I have recently been introduced to Crack-it Freeze spray as an extra aid to freeing off stuck items. Give it a few good long sprays to get the bolt really cold, it might just help.
https://www.screwfix.com/p/arctic-hayes-crack-it-shock-release-spray-400ml/83415?tc=WT2&gclsrc=aw.ds&gad_source=1&gad_campaignid=19822796606&gclid=Cj0KCQjwk_bPBhDXARIsACiq8R1iHRsl2blGGAk2GTjHBhCjjSndKfHOLhk4OB3LwozkePYnQJLlnK8aAtLaEALw_wcB
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very interesting will need to try that
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Just to say itās great to hear such attentive advice, some real gems in that conversation.
I have just been struggling, in a far less, but also frustrating way, as the 3 mm Allen key bolts holding the plug covers tight. I treated my bike to a 30000K service at a dealership in Wellington NZ and now 6 k later they were a problem, I think it may have been due to an overenthusiastic mechanic, as I couldnāt see rust, but I was damaging the hex heads.
After a period of penetrating oil, warming the engine and tapping, they finally crept loose, Iāve never heard of ā crack itā but Iāll be sending off for some now!
Iāve replaced with Stainless Steel and nickel slip.
Well done lads a good read
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Also avoid ball-end allen keys as they will strip out the hex head as quick as you like.
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Just had the same issue with the plug covers on my Mandello. Now replaced with better quality aluminium fasteners. Kinda ridiculous on pretty low stress parts. This just after having two brake disc bolts shear on me. I think itās a bit sad on a āpremiumā machine to expect low cost cheesy fasteners that are unable to withstand normal dismantling with good quality tools.
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Guzzi had their own special cheese only used on certain parts.
Maybe Aprilia bought Guzzi to get the patent because they use that cheese for many more parts on Aprilia as well as Guzzi 
.
Thats why I have a set of hex sockets just in case and i donāt use ball end allen keys 
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Love my Hex and Torx sockets too! 
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