R1150GS very lumpy idle - what's causing this sound?

craagens

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Hi all,

This is my first post, also about my first motorbike! I'm in the south, 30YO, and passed my direct access during lockdown. I bought a 2002 R1150GS from a work colleague a few weeks ago (as a project / non-runner that I can fix up and learn with) so I've been working away to get it back on the road.

The bike's previous MOT expired in May 2014, it's been sat on a driveway and sadly took some rainwater into the tank which caused a lot of rust. I've spent the last few weeks renovating the fuel tank (I'll make a separate post detailing that) and today was the first time I turned the bike on to see if it would tick over. After the new fuel pump got fuel to the injectors, the bike can idle but it is very rough and lumpy. It sounds quite bad, and I don't know the internals well enough to know where to look next. In fact, it sounded so bad I only ran for 30 seconds before turning off. I haven't changed any of the oils yet (they arrive this week) so decided I should probably at least wait for that, and seek your advice on the noise:


I've checked the throttle cables are seated on the throttle body. Pulling in the clutch doesn't change the sound either. What should I check next?

Cheers
 
That seems very likely to be my issue, I will investigate! Thank you

STOP - have look in the sticky at the top of this section - tips and info . Look at the “why is my bike running rough - a common fault” post ..... here’s a clue .
 

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Neil
To his credit, the OP says he has already checked that particular issue


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That sounds...... Not good

Are both header pipes getting equally hot ? (Be careful)

Does it get better as you rev it ?

Is it on both sides or just one ?

I am also thinking that you should be looking at your Cam Chain tensioner/Guides.

Have you got enough oil in the bike ?
 
I found some time to take out the old LHS cam chain tensioner bolt and the valve cover to take a look at the guides. Sadly it's bad news!

- The piston and spring for the old CCT bolt have fallen down into head. When I put a long magnet down the hole for the CCT I was able to contact with the chain itself!

G1dWSOU.jpg


I am led to believe that the cam chain is certainly broken because:
- The CCT 'piston' and spring were not where they should be - I can see the rogue spring underneath the chain now, I guess the CCT piston is there too. I've ordered an endoscope to verify.
- A long magnet down the CCT bolt hole was able to pick up the chain.
- Looking down the chain (after removing valve cover) I could see that the chain has been contacting the metal cylinder casting and has cut away two small indents which match the 'H' shape of the chain.
- I could see the plastic fixing where the pin goes through, but no plastic above the chain. But I might be mistaken, because it's a very tight space and I don't have an endoscope. I've ordered one so can get a clear look inside soon.
- The CCT is the original 17mm head bolt which is known to underperform. Combined with being sat for 6 years, I am sure that my recent firing up of the bike has broken the guide.
- It sounds awful. I believe the audible metallic noises are indeed the chain slapping around and contacting with the head casting, since there is no guide to be seen and certainly no CCT spring in action.

@MotoRevive - both headers get hot, the bad sounds match the revs and didn't get much better, I can't really tell if it's both sides, and it does appear to have a lot of oil although it is very old at the moment.

What would you recommend next? Attempt to (or pay someone to) dismantle the heads, replace the CCT guides and rebuild the engine? Find a new engine? I picked up the bike for £800 (including touratech panniers and a top box) and have spent around £300 on service parts (many not fitted yet) so I'm not that deep yet.

Interested to hear your thoughts
 
Talk to Steptoe

I suspect a low..ish mileage engine from a breaker will be the cost effective solution. Resist running yours, in case the cam chain jumps & you wreck the whole thing, then you can keep it for spares icon.
 
You most definitely need some engine work. You don't need me to tell you that.

Your guide is broken as is your CCT. If your chain is damaged then it needs replacing. You can't remove the chains without splitting the engine.

You need to be sure it's broken. You can rotate the engine and check it carefully.

You can change the guides if you remove the gearbox, clutch and flywheel. It is tricky but possible. CCT isn't a problem.

If you need a chain, then you need to split the cases.

It's up to you whether you install a second hand "Unknown" motor which may have all sorts of problems waiting for you or you can rebuild your known motor.

It's not going to be cheap though.

Where are you based ?
 
Damn shame this happened, especially as it's the OP's first bike.:blast - 1150GSs should normally be considered a fairly sound buy. I'm sure you could get an estimate for fixing it, but it would likely be more than you paid for the machine. I think you'd be better cutting your losses and breaking the bike, you'll probably get most of your money back, or even sell it whole then start again with a bike that runs. Changing the motor for another is a pretty big job...
 
Not sure how to edit my post, I meant that "I am led to believe that the cam chain guide is certainly broken"

I can see the chain on the cam wheel so I suspect that your camchain is actually okay and it is just the Camchain guide and tensioner arrangement

Whilst you probably do not want to spend a lot of money on this

Getting Professional help at this stage, Even it should only be a confirmation of diagnosis and advice on how to repair the problem But better still the problem repaired!

Why not book in with Steptoe and get him to cast his eye over it I don;t know how much it will cost? But a couple or three hundred quid spent with Neil may well sort it to the stage that you can get on with riding it !!

He has old and wiley ways to do stuff that folks can't imagine
 
I'm surprised that non of the aftermarket suppliers have offered a replacement cam chain in situ option?

i know on the old Saab 900 turbo range everything was back to front, and cam chains were one of the foibles of the engine

The correct way was engine out and chain replaced = big bucks

then some of the after market suppliers offered a split chain and replacement rivet option.

All you did then was punch out a rivet, link the new chain, turn the engine over to take round the sprockets, and then when the new chain reappeared re

riveted the ends together.

I think it turned a £1500 repair into a £200 option

It makes you wonder if the original seller knew of this fault - hence the non runner status
 
I'm surprised that non of the aftermarket suppliers have offered a replacement cam chain in situ option?

i know on the old Saab 900 turbo range everything was back to front, and cam chains were one of the foibles of the engine

The correct way was engine out and chain replaced = big bucks

then some of the after market suppliers offered a split chain and replacement rivet option.

All you did then was punch out a rivet, link the new chain, turn the engine over to take round the sprockets, and then when the new chain reappeared re

riveted the ends together.

I think it turned a £1500 repair into a £200 option

It makes you wonder if the original seller knew of this fault - hence the non runner status

yep lots of jap bikes come with a soft link to rivet/peen over ..suppose its bmw oh new chain thats an engine strip =£££££'s or why not buy this newer model ..
 
Your guide is broken as is your CCT. If your chain is damaged then it needs replacing. You can't remove the chains without splitting the engine.



If you need a chain, then you need to split the cases.

Oh no you DON'T

I'm surprised that non of the aftermarket suppliers have offered a replacement cam chain in situ option?

i know on the old Saab 900 turbo range everything was back to front, and cam chains were one of the foibles of the engine

The correct way was engine out and chain replaced = big bucks

then some of the after market suppliers offered a split chain and replacement rivet option.

All you did then was punch out a rivet, link the new chain, turn the engine over to take round the sprockets, and then when the new chain reappeared re

riveted the ends together.

I think it turned a £1500 repair into a £200 option

It makes you wonder if the original seller knew of this fault - hence the non runner status

yep lots of jap bikes come with a soft link to rivet/peen over ..suppose its bmw oh new chain thats an engine strip =£££££'s or why not buy this newer model ..

See above :D

You can also replace the guides without splitting the engine. I've done quiet a few and know others have also done the same.
But i can't be arsed now due to getting grief from someone while trying to saving him a huge amount of money.
 
Oh no you DON'T





See above :D

You can also replace the guides without splitting the engine. I've done quiet a few and know others have also done the same.
But i can't be arsed now due to getting grief from someone while trying to saving him a huge amount of money.

With all due respect, I will NEVER use a soft link cam-chain on any of my customers bike. There is a very valid reason that NO manufacturers fit them or will sell them. Because a non-factory fitted link will always be a potential weakness.

I know you can buy them and I know many people have used them in the past. I've also got an industrial unit full of destroyed engines where people have short-cutted repairs to save money. And quite a few engines with snapped cam chains of this type.

I probably would on my own bikes. Because I can remove the covers whenever I want and check the links.


For me it just isn't worth the risk in my business. Obviously it's a personal choice and I won't get into a lengthy discussion about the pros and cons of it. But for me, it's a NEVER.
 
With all due respect, I will NEVER use a soft link cam-chain on any of my customers bike. There is a very valid reason that NO manufacturers fit them or will sell them. Because a non-factory fitted link will always be a potential weakness.

Yup Also the manufacturer is building everything from the cases up so split link is not necessary

IN reality though, these two chains are just spinning a camshaft each, Not exactly high tension ??

I've used quite a few over the years I've been spannering and no failures But then again most of the folks I did work for were sensible souls who did not thrash something to within an inch of its life

I am still not convinced that the OP's bike needs a cam chain I can see it sitting nicely around the cam wheel

I think it just needs a cam chain tensioner blade!
 


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