swing arm

[Guzzidave]

hi to everyone ,im new to this site and need some help ,
I removed the rear wheel on my pcx 125 to have a puncture repaired , the upper swing arm bolt towards the front of the bike was already loose and upon removal I found the thread in the aluminium casing to be stripped , will this either A. tap out to M12 B. is there room at the back to place a longer bolt and put a nut on the back or C is a helicoil the only solution , I don't want to go down the new casing route as this is my commuter bike used every day , any thoughts will be appreciated ,

also fantastic little scooter a real pleasure to ride

[aguim]

One of many solutions, a simple one :7/16"=11.11mm. You could 7-16 tap that bolt hole, 7-16 drill the swing arm, then use a 7/16x1.5" bolt. The original M10x40 was probably overtightened?

I use to repair 12mm aluminium crankcase drain bolt holes using a 1/2" tap (12.7mm), no
problem. Just don't overtight these...

[u33db]

There is another option but I've not tried it yet.

You can get brazing rods called "HTS 2000" where you can repair alloy - i.e. stick the bolt back in then melt this material in to reconstruct the threads or any other damaged alloy section;

https://www.aluminumrepair.com/

On one of the sites they even use the stuff to repair a broken lug on a car gearbox!

You can buy kits from various companies only quite cheaply (like £30)...maybe an option?

[you you]

There is another option but I've not tried it yet.

You can get brazing rods called "HTS 2000" where you can repair alloy - i.e. stick the bolt back in then melt this material in to reconstruct the threads or any other damaged alloy section;

https://www.aluminumrepair.com/

On one of the sites they even use the stuff to repair a broken lug on a car gearbox!

You can buy kits from various companies only quite cheaply (like £30)...maybe an option?

Good luck with that one

[Guzzidave]

thanks for replies guys , ill see if I can get a 7/16 " tap and bolt ----- should be easier to obtain now we are leaving Europe

[Alibally]

I would get helicoil kit. I've used them successfully before with no problems.

E.G.

15 Piece Thread Repair Kit M10 X 1.25 X 13.5mm https://www.amazon.co.uk/dp/B007QWQVZS/ ... YybVX6JZ35


You just need to get the correct thread size for the bolt you are using.

I wouldn't re-tap it bigger. If it doesn't work then your looking at a new casing.

[aguim]

There is no reason why going from 10mm to 11.1 (7/16") shouldn't work. Cheap and easy for
anybody with minimal skills. If you're unfit to do it, better not mess with an helicoil installation.

[Guzzidave]

i have got a 7/16" unf taper and plug tap and a hex head bolt , had to make an extended tap wrench so will bash on at the weekend , should be a good fix ,
thanks again for all the suggestions

[aguim]

I'd prefer 7/16 UNC...less chance of "packing up" with aluminium (use cutting oil or grease
and you should be good, though). If you feel too much resistance, back off and 'clean' the
hole with a round, rough file, a bit.

[tomtomclub2005]

I installed helicoils on the threads holding the front caliper- they were just too fragile and strip too easely after just a couple of removals of the bolt. It's a straightfoward and permanent solution, Kits are not too expensive.
Yes, You could simply tap the thread and install just a bit bigger instead, but that might strip again sooner or later, when you install a new tyre or change your drum brake pads...

[Alibally]

I've repaired cylinder heads with them. The helicoils are stainless steel and are stronger than the alloy threads.

[aguim]

Yes, helicoils are tops. But sometimes not really necessary. Ex: I once bought on-the-cheap a
Kawasaki Ninja 250 whose cam cap bolts threads had been botched by the overzealous PO. I considered helicoils, but decided instead to use an 1/4-20 tap (.35mm bigger only) then a tad longer bolts. Good for the next 5 years/65,000 more km...

I had the tool at hand, saved 60$. Why not.

[Guzzidave]

for future reference ,
I made an extended tap wrench from 20mm dia tube with a 5mm thick 6mm square holed washer welded to the end (pictures supplied if needed ) and the hole tapped out 7/16 unf , all the way through , the swing arm hole was already 11.2mm so didn't need drilling out , all in all a good job well done , so thanks for all the input , job was completed in 45 mins from start to finish