Honda CBR 125R R7 Engine

[MitchCBR]

Afternoon All,

My cylinder head on my bike broke the other day (the cover I think, it broke where the bolts go for the exhaust) trying to take the exhaust off and I've been kinda stuck with what to do! I've considered all sorts, like just scrapping the bike, getting a garage to fix it (3 month waiting list apparently) getting the parts and getting a friend to fix it and I'm now thinking of just getting a brand new engine put in it instead of fussing about replacing parts.

I'm wondering if a different year bike engine would work in my bike, as mines a 2007 and the only decently priced one I've found is for a 2006!

Feedback please??

Also if you have anything you can contribute to get me unstuck I would appreciate it! I'm skint as it is and the stress is just taking its toll on me, as I need the bike to travel

Thanks in advance..!!

[Grumpy Old Git]

Exactly which part(s) is broken?

If simply the cylinder head - a breakers / fleabay have these usually (NB. You will need a new gasket).

If the exhaust stud - Use an extractor / drill to remove and replace.

Exhaust flange - just replace.

All fairly easy fixes.

If it is the actual barrel you have broken, then a replacement top end / 2nd hand engine is needed.

Pictures would help.

[Richtea]

Three month wait where in Halifax you taking it.

Give us a good description of what's wrong an I might be able to sort it, I'm only in Huddersfield and so not a million miles away and I'm cheap I work for beer lol

Failing that the guy who does my bikes is reliable an relatively cheap I can pass on his number

[MitchCBR]

Basically when removing the exhaust, one of the bolts sheared the head, and another... how to describe... well it came out, but it tore through the wall of the aluminium and ripped off a chunk of thread from the case.

I don't have any photos so i cant show you what's up with it!

[MitchCBR]

This is what happened to the other Threaded hole

(my modelling skills coming in handy!)

[Richtea]

So one bolt is snapped in the head and the other is out but broken the casing as your picture ?

If so the broken one will probs drill out as for the broken thread not too sure without seeing it.

[MitchCBR]

I have a picture now.

[megawatt]

So you are thinking of scrapping an engine because you sheared an exhaust stud and cracked a small piece of alloy off the head? Sheash!!! Do you have a lot of cash to throw away?

[MitchCBR]

No, I just don't have a clue what it is I'm looking for to replace it, I'm new to bikes and don't fancy taking one apart on my own, knowing me id f**k it up more.

plus its there's a lot of corrosion, so if it got took apart I don't know what else would be corroded, don't wanna take the engine apart to change the case, and find out I cant put it together because something else broke.

[Mr Fro]

There look like there's enough meat left on the snapped stud to get it out with some mole grips - after a liberal coating with WD and maybe a tickle with a blow torch (not at the same time of course!).

If it were me, I'd be tempted to try and get the broken bit welded up - not a big job if you've got the broken bit but will require a bit of fabrication if not.

[MitchCBR]

That's what people have said, but i don't know if i have the other part of the broken hole :/ so i need to buy a new one, but as i mentioned i don't have a clue what it is im needing to buy!

[Adam]

Go to a local welder and fabricator they'll sort it out for you. And it will cost you a fraction of what a new engine would cost you!!!

[Richtea]

As above soak the broken stud with wd40 for a couple of hours then remove with mole grips and a bit of heat if needed.

As for the other side you may be able to drill it a little deeper ( be carefull ) then thread it out.

To stop this happening again refit exhaust studs with a thread on either end and brass nuts available at halfords and most motor factors.

If they seize again all you do is cut off the brass nut with your trusty dremel !! easier than the above problems in the future.

[MitchCBR]

Cheers for all the advice guys! i finally got a straight answer of what parts i need to order from a supplier so ive got them on order and will be getting them next week!

hopefully a friend of mine might be able to fit them, if no i might have to take you up on your offer Richtea of working for beer (if it still stands of course )

i can now relax