GN125 engine problem

[Ricco1]

First, apologies for the length of this post, thought I'd give as much information as possible.

My bike is a Suzuki GN125 2006. It's done 15,000 miles, I change the oil and filter every 1500 miles.

Last week my bike developed an engine noise. The best way I can describe it is a clicking or rattling sound. The higher the revs the faster the sound, if that makes any sense. I took it to my local bike shop. I've used him before, he's helpful and reasonable. He suspected either tappets needed adjustment or otherwise, loose cam chain.

I left it with him, he called someone else for a second opinion. He said tappets and cam chain are fine therefore it's a lower engine problem, very likely to be the big end bearing.

He suggested that the cost of fixing this would be very high, I'm better off getting a complete engine off a write off rather than having the work done.

There are a couple on Ebay for £330. These have short warranties. £50 to fit it so we're close to £400.00

I'm hesitating to do this, I'd like other opinions if possible. If I buy another engine I won't know its condition or whether it's been regularly maintained. I could buy a pig that could pack in in a few months or whatever.

So what should I do, what are my options?

Many thanks

[Mr Fro]

If you're handy with a spanner you could change the bearing yourself.

[Ricco1]

Although I like to have a go at things I'd be right outside my comfort zone if I had a go. And my tools are limited.

Is it worth taking it to another shop to get a second opinion? Anyone know an enthusiast who might like to do this work? Or any other options?

[Tango]

Put your location in your profile....there may be someone that knows bikes on here that's local to you and wouldn't mind taking a look.....

[Ricco1]

Right I'll update that but in the meantime: I live on a narrowboat (bike on the back) in north east Cheshire. Macclesfield/ Poynton/ Marple most of the time. Can travel but on a narrowboat, it's never fast!

[V1P3R]

Ooh narrow boat, jealous! Any other boaters or someone at a dock able to fix fir backhand bit of cash?

[Tango]

2006 bike regularly maintained knackering out the main bearings?.......hmmm.....I'd deffo be looking for a second opinion on that!!

[Ricco1]

I'd like a second opinion but short of stripping it down, how can anyone form one? And of course the stripping down takes so long...

[eastanglianbiker]

start it up and use a piece of wood against the cylinder head and your ear against the other end of the wood see how noisy it is then do the same on the barrel and then on crankcase that will help you work out of tapping is top middle or bottom end

[Ricco1]

Thanks, I tried that, it wasn't conclusive.

Does anyone know a rough figure of how much it might cost to have the engine rebuilt? If a bike shop isn't competitive, are there places you can send the engine to who specialise in this type of work?

Thanks again

[eastanglianbiker]

anyone any good with a socket set a spanner set and a haynes manual are capable of doing the job

[Ricco1]

Update on this: I took it to another shop. He had a quick listen and said it was almost certainly either the cam or rocker or combination of. These engines are Chinese, he says the quality of metal used is poor, these going is a common problem. Does this sound plausible?

[eastanglianbiker]

it would need the cam cover removing to confirm and internal cam/rocker failure and to go any deeper would mean removing the cylinder head and barrel to check play in big end properly

[Bogof]

Update on this: I took it to another shop. He had a quick listen and said it was almost certainly either the cam or rocker or combination of. These engines are Chinese, he says the quality of metal used is poor, these going is a common problem. Does this sound plausible?

 

Suzuki using Chinese engines? Whatever next...

Whichever way you look at this, either you or a shop need to strip it to diagnose properly. If you can't do that, ask a shop to strip it, diagnose, and report their findings before they carry out any repairs.

[Grumpy Old Git]

it would need the cam cover removing to confirm and internal cam/rocker failure and to go any deeper would mean removing the cylinder head and barrel to check play in big end properly

 

The first step - removing the cam cover - is 'easy' and will enable a check of the cam operation and chain tension. A decent garage should be able to do this check for you quite cheaply (ask around your area).

Personally I would just do it myself (Haynes or OEM Workshop manual and a few decent tools).

Removing the head and barrell is also quite easy provided you follow the steps in the manual. Then it is very easy to check the big end (and small end) play.

If (and only if) it is a big end issue, then the engine will need to be stripped down/split to allow the bearing to be swapped out - Not so easy if you are not 'comfortable' using tools, etc. BUT this should still be cheaper (and less 'risky') than buying a replacement engine.

Good luck with this.