JB WELD

[veroom]

While I struggle to find a local TIG Welder which would be the best thing if it doesn't or can't warp the cylinder head, I am totally stuck on JB Weld.

I get it to some degree, in a standard environment, done properly, it can be bloody good stuff but for me, there may be a risk of damage to the cylinder head if I don't go the JB Weld route and have it welded. Granted, it's not exactly right next to the cylinder but a gamble by all accounts.

This is in relation to my other thread that exposed a problem with my NSR 125 exhaust port where the stud holds the downpipe. https://www.bikechatforums.com/viewtopic.php?t=297855

I have highlighted the damage, the alloy is cracked across the stud hole.

https://s22.postimg.org/q5kpf1apd/damage1.jpg
https://s22.postimg.org/sbf09je5t/damage.jpg

I can't afford to replace the head. I'm struggling to find a tig welder but the holiday hasn't helped I guess. I'm told it can be welded quite cheaply but getting that sorted seems tough right now.

I live in Oldbury nr Birmingham and this bike is my road to license and a big charity bike ride that is in planning stages later this year so any genuine help is inevitably for a good cause having raised over £3,000 and building a mountain bike worth £900 that is to be sold off for charity. (Terminally ill children)

Thanks in advance. I am a true novice here.
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GSXR 600 - Got bike, must pass test, wish me luck.

[Pete.]

No, it's not designed for cylinder heat and it'll really annoy the welder when the time comes to do it right.

Looking at your damage there seems to be a couple of failed attempts at repair.

Your 'cracks' look like hack-saw marks where someone has tried to put a cut across a broken stud to try to remove it with a screwdriver which almost never works and makes drilling the broken stud out ten times harder.

Then it looks like someone has tried to drill out the bolt and the drill has run off into the ally. In the pic it looks like you have the bottom of a half-drilled stud in the hole. Looks like they gave up on that to and resorted to tapping the shallow top half of the hole over-size.

If you remove the cylinder and post it to me I will repair it and send it right back FOC. You can be sure that the repair will be properly done and last the life of the bore. all it will cost you is one-way postage and a top-end gasket set.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Boxing]

As above. Wouldn't even bother applying JB weld there. If you don't send it off to Pete, take it to an engineer, they'll be able to weld.

Aluminium is very tricky to weld onto, and it'll have to be very clean or it won't work.

Pete has offered a very nice gesture, and I'm guessing that'll be your cheapest option for the proper job. He rebuilt Paddy's RS125 engine a while back.

[veroom]

ferkin feckin fookin hell pete, that's very kind of you mate.

I'll pm you in a bit to get the details. Really not sure I can thank you enough bud.

I was about to order some when I felt to post this instead. Granted, the JB is only 4.75 but that's not the point in this situation is it.

humbled sir, thank you.

I'm guessing JB is excellent for some solutions, just not things like this. Thanks to you too boxing, for the reply. I shall sort this out get it in the post tomorrow.
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GSXR 600 - Got bike, must pass test, wish me luck.

[kestrel]

[Boxing]

Don't forget, genuine gaskets. Topend is four bolts. Use a ring spanner and not a wrench on them.

Look up the recommended torque pressure for the topend bolts for when it comes back also.

Now will be a good time to check your piston and any play in the conrod.

Don't forget to put tissue around the bottom of the piston to stop spiders and dirt getting into the bottom end.

[veroom]

Defo Kestrel, I just have to sort getting the cylinder off. Just pee'd the mrs off, moved the kitchen to bring the bike in (we have a long kitchen) so I can do it in the warm and dry.

Boxing, a little unsure of the gasket kit mate, got any tested sources for them ? I can see two of them on pjme

https://www.pjme.co.uk/acatalog/Honda_NSR_125R_Engine_Parts_Top_End.html

one is out of stock, nether say genuine.

Gonna have to find out the torque settings too, I have downloaded the manual.
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GSXR 600 - Got bike, must pass test, wish me luck.

[Boxing]

It depends if you're doing the head gasket as well. You shouldn't really need to removing the cylinder, just the base gasket to go between the cylinder and the bottom end.

Athena do good quality ones. At least from the ones I've tried for the Yamaha DTR.
It's how you apply it that'll tell you how good it is.

Be wary on taking the topend off in your kitchen with it being water cooled. Even if you drain the whole system, there'll still be them couple of drops in the pipe when you take it off. You should only need to remove the four bolts at the bottom of the cylinder. But you can take the head off as well it wouldn't hurt it, you'll just need a new head gasket. (Note: If you don't drain the system prior, it'll leak all the coolant inside it over your floor.)

I know this isn't your bike and your engine is still in the frame (still just as easy) but here's a video to lend you a helping hand. https://www.youtube.com/watch?v=6If62yhyfqc I personally won't remove the head, unless you find out the top end is on its way out and you need to send it off to PJME. Also, don't remove your piston or rings lol.

Edit: Forgot to add in, you'll want to take the four bolts off in a diagonal pattern. E.g left bottom, right top. Only for the first undo / "click"

The gasket on the PJME site this one:

[veroom]

Yea, sounds about right Boxing. I couldn't order that one cause you have to spend £10 and since I don't need anything at this stage I eventually sourced this one

https://www.hondascooterspares.co.uk/product/honda/12191KY4971/gasket,cylinder?uID=0

Just under £6 free p&p

I did change my rad on my old rs turbo some years ago so I am somewhat used to playing around. That was needs must like this so I have a bit of confidence doing it.

Is there anything special coolant wise ?

No engine oil issues ?

Guessing I have to detach accelerator and choke etc from the carb right ?
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GSXR 600 - Got bike, must pass test, wish me luck.

[Boxing]

[bladerunner]

Just for info David silver spares are listing new genuine barrel and piston sets for £155. Is it worth spending the extra in the long run?
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Current bikes...cbr929, KDX200's, Rd125lc mk2, RGV250's

[Pete.]

If that includes rings that's a really good deal I say. New-bike compression for £155 is not to be sniffed at.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[bladerunner]

Just for info David silver spares are listing new genuine barrel and piston sets for £155. Is it worth spending the extra in the long run?
____________________
Current bikes...cbr929, KDX200's, Rd125lc mk2, RGV250's