Hi everyone i wanted to post on here as I love the advice everyone gives an makes u feel friendly. Ive brought the missus a honda cbr 125 as she wants to hit the road haha. I brought it as a none runner as got it really cheap they told me it needed a new engine so I said to the missus ill have a little play with it worse case we get a engine so was worth the risk of opening it up today and here's where the problem is the piston is shatted see pics ive been watching and reading online am I right in thinking it just needs a new piston and pin? As I sent a pic to a mechanic and he was saying ouch that looks a massive job or is he just wanting to pull my pants down. Also there's bits of piston broken inside the engine hows the best way to clean all the bits of metal out so it dont damage anything moving forward thanks again for any help also hope ive posted in the right place
I suspect that will be an uneconomical engine to repair. The shattered piston parts still have done untold damage to your bore, crank, head, and bottom end. There will be lumps of piston in oilways, gears and anywhere else as it went with a whizzing bang. I'd pick up a fresh motor from a crasher and drop it in and maybe salvage some undamaged spares from your motor. I picked up a dirt cheap nx650 years ago that had a snapped chain, shattered gearbox casing and ruined gears. I enjoyed the build to be honest, picked up a motor and built a good engine from two. I ran it for a while and moved it on.
Thanks everyone for ur replys so its best to look down the road of changing the lump if so do I need to stick to the same year or will other models fit this 13plate cheers for ur replys
As above - you could not just refit a piston I suspect it will have damaged the head and you have metal debris in the engine The only way to know for sure is to completely strip the engine and box and clean every single part and inspect for damage. Also - why did the piston do that - running weak - getting hot?... so you need to fix that too... could be someone fitted performance exhaust and its running lean - could be fuel problems. Is it the Water cooled version ? I think so at that year - so maybe there is a cooling system problem... so even with a new engine - make sure that is OK too...
Wouldn’t know on that bike but if you can find identical bike at breakers the engine change should be fairly simple - as above though pistons don’t usually just pop
I think they used same engine between 2011 and 2017... but not 100% certain there was no small changes.
