Hi guys

Is there a specific tool to remove the 2 front flanged nuts on a cylinder?

I can get a 13mm spanner on but it can't rotate enough before the back of the spanner contacts the case. I'm now starting to round the unit Iv messed with it so much!

Frustrating as I'm the 2 front bolts away from checking the bearings and rebuilding the top end!

Cheers

Andy

You didn't mention which bike. Regardless of that I've a few ring spanners that I've had to grind/relieve the profile of to get into corners. Give that a try.

It's a 2014 GasGas 300 racing. I tried to grind one down but it just opens up now as it's no strength and then adds to the rounding off!

Dont be insulted when I ask you to check you are turning the nut anti clockwise. If it's started to round off, try forcing an imperial ring spanner on, or even an open ender if there's enough room, just to crack it loose. If that fails use a die or angle grinder, if there's room and carefully shave down the side of the nut till it just cuts through to the stud. The remains of the nut will now unscrew. Obviously a new nut will be needed and possibly a stud.

I use a 1/4 in drive socket and a universal joint attachment. You could try one those flexible drives too.

Paul Mac

You could also try an appropriate size socket from a screw driver bit set and grip the tang with a mini mole wrench. Not the most elegant of engineering but it works.

if you've not had the head off a gasser before the o rings can be a bit temperamental. Get new ones, give em a slight stretch and coat them in a little grease to help em stich in the groves and all should be cool

Paul Mac

Im presuming by your comments you've ground down the open end of the 13mm spanner you are using? Turn it round or use a ring spanner instead and grind down the ring end to fit. Make sure you use the star ring spanner with lots of small contacts instead of the ring spanner with only 6 sides as you can get the spanner on in more places. Thats what i did when i refreshed the top end on my gasser and it worked a treat. The ring end of the spanner will be quite thin but will have enough strength to undo the nut. Hope you understand what i mean and hope it helps.

Hi all

In the end I had to grind the nut off. The problem was that the stud had corroded quite badly so I had no chance of getting it off!

I'lL need to replace the stud but that's not a big deal.

Thanks for the help guys.

Andy

Andy,

The fact that a 2014 bike had screwed fasteners that could not be dismantled conventionally, would seriously concern me. It's only experienced one winter. I think I'd systematically dismantle as many components as possible and apply copperslip or molybdenum disulphide based grease. Swinging arm & engine removal are much more of a chore with seized fasteners, removal of both being predictable. I thought build quality had improved, over the years.

Sounds like it's had a hard time if you're refreshing the top end and struggling with seized fasteners.Id go right over it and grease all the bolts and linkage bearings,do you know it's history?Preventative maintenance can save a lot of grief later on

Actually the new cylinder has more room than the older pro`s. A thin wall socket does the job, or higher end wrenches usually are thinner than what most home mechanics have on hand. I do not think you need a top end. Try changing your jetting (Too lean on the pilot) and higher octane fuel. I`ve never hadto cut a nut off a trials cylinder. (And I`ve worked on a few bad ones) I hope the stud comes out clean. Good luck!.