2006 XT600E piston slap, or worse??
 

Hi all,

I recently bought a mint 2006 grey import XT600E with 2400km on the clock - just out of warranty. I noticed a couple of the silencer mounting bolts were missing (the previous owner had presumably fitted a slip on can) and I attributed a heavy rattle/knock to the loose exhaust. I recently replaced/tightened the offending bolts and now strongly suspect the noise I'm (still..!) hearing is piston slap and/or small/big end bearings.

The noise is present at standstill and on the move. A light blip on the throttle from idle seems to reproduce it quite consistently. Oil level and appearance is fine and the gearchange is smooth, so I don't think it has seen catastrophic lube failure.

Is slap common on XT6E's and would I need to take any precautions if a re-bore was required, i.e. is the bore hard plated, etc.?

Finally, if a complete strip is required, are there any sensible mods out there to improve reliability/durability? I intend to use the bike for long-distance overland touring so it needs to be bombproof!

All comments greatly appreciated.

Cheers,

Andrew S

slap?
 

Never heard piston slap on a XT. Difficult to diagnose a noise over the Hubb of course.
Try to locate the noise with a screw driver, handle in your ear, bussiness end to the engine.

Seems unlikely that at this age and km's the thing is worn out. Especially as main and big end bearings are ball / roller bearings, as far as I know they do not make the same noise when worn as journal bearings do. For the big end, normally the noise increases with engine speed and load; if it does not, that's not your problem.

One thing comes to mind; Yamaha sometimes forgot to tigthen the nuts on crankshaft, balancer shaft, clutch sufficiently. All produce a knocking sound, all behind the RH engine cover.

The cilinder is cast iron, so no nickasil or other exotics - just rebore, oversize piston.

Sensible mods - no, your 2006 XT is as good as they get.

Auke

No two bikes are ever EXACTLY the same. The bike you have procured has hardly been run in let alone used for any disernable time! I would be very surprised if the noise you have described is terminal or indeed serious enough to be really concerned. The XT6 is quite simply legendary in terms of it's engine reliability and it's utter simplicity. Without teaching you to suck eggs, the bike is a Single cylinder and it is well known these engines suffer from excessive vibration compared to multi-cylinder engines.

Are you 100% sure this noise is eminating from the engine itself and not somewhere else?

Other than this noise is the bike displaying any other adverse symptom with regard to operation and performance? If not then I'd be tempted to ignore it (providing of course it doesn't become excessive).

The bike you have is capable of doing almost anything well. It is quite simply legendary in terms of RTW travel. No need to change anything at all. Keep it standard. Some people do make these changes though -

a larger fuel tank
a more comfortable seat (or just put a NZ lambs wool cover over the seat).
S/S brake hoses

Thanks for the feedback guys.

No, the noise is definitely not normal big single cylinder thumper noise and yes, it is coming from the engine. I haven't had chance to try the improvised stethoscope yet, but will try to do so at the weekend. Failing that, it will be dispatched to the local Yamaha stealer for a health check.

Further web trawling turned up this from Greece:

2003 Yamaha XT600 review from Greece

"Got to see.."

What things have gone wrong with the motorcycle?

When I bought the bike, oil leaked from two caps, but the problem was fixed on the first appointment.
When the engine warmed up, a ticking sound was heard as if the valves were knocking. After 3 fruitless visits to Yamaha dealers, who adjusted the valves, the problem was fixed at the official dealership's workshop. It turned out to be large gap between the piston and cylinder, resulting in piston slapping on the cylinder walls. Later I found out that many later XT models had it, due to old [COLOR=#006400! important][COLOR=#006400! important]cutting [COLOR=#006400! important]tools[/COLOR][/COLOR][/COLOR] used in the Yamaha production line!! Of course it was covered under warranty.


I wouldn't describe the noise I have as a "ticking", but an interesting read nonetheless.

I may have similar symptoms, a slight blip of the throttle also produces more of a knocking sound.

Sorry to threadjack but aukeboss, how would I go about checking those loose nuts you mentioned? an engine out job? special tools? Thanks!

...a possibile longshot perhaps, but....

I cant speak for the later XT's such as yours, but certainly in my experience with the 80's genre, the primary drive gear located just above the oil filter was located and fixed with a woodriff (sp?) key that was prone to distortion and failure. This created a knocking sound as the tolerance gap widened and also had the tendancy I believe to offset the balance gear which added vibration. It's a simple check well worth doing before dropping the engine and removing the head. .....Obviously check the manual to see that you do have a key there on your model.

easy
 

Remove RH engine (clutch) cover. Normal tools required.
Check torque on the mentioned nuts.
For the primary drive nut a large socket is needed - 56 mm or smthng. For the rest, a torque wrench of course.
To hold crankshaft in place while torqueing: copper ring between the gears on crankshaft and balancer shaft.
To hold balancer shaft while t-ing: hold nut on crankshaft
To hold clutch shaft: shift to second gear. Fix rear wheel with sturdy strap

Consumables: cover gasket, retaining clips for the three nuts, or re-use, one lip on each might still be unused.

Auke

Hi

I used to have a Yamaha SZR660 , this had a knocking noise which I was vainly hoping was piston slap but it turned out to be the big-end gone. I found it was very difficult to check the oil level via the oil tank/cooler contraption and so may have inadvertently ran it low on oil. Best get it checked out.

Regards

Robin

Seized engine
 

Just to give you an idea, I have the 600a (similar to the E but kickstart only) it's probably an in-between model, not sure.

I had an oil problem recently, the mesh filter in the frame was blocked by the previous owner using pipe sealant on the nut. The crankcase pressurised dumping all the oil through the airbox. Unfortunately I was doing 70 on the motorway when the blast actually happened, the oil didn't cause the problem, more the lack of it.

I ended up heat seizing the motor. Initially I thought it was the big/little ends that had seized but after a stripdown and replacement crank I still have the piston slap.

So it's no choice now but to buy the new piston and a possible rebore.

If it's any help, I've put videos on youtube of the strip and rebuild, it should give you an idea as to what you're up against.

Just do a search for 'binferweb' there's 25 individual vids

Have a look at my webpage for the manuals

Binfers XT page

Your bike is REALLY low mileage...

Although not technically impossible, the chance of it being piston slap or main bearing are very very low.

Bare in mind, if you have come from riding newer 4 cylinder bikes, then the noises of a 20 year old large single cylinder bike can make any rider paranoid.

I would be systematic with your search using Aukeboss's pointers to start with...

Maybe consider comparing it with another XT600E or take it to a dealer for an opinion.

This thread is from 2008

grrrrrrrrrrrrrrrr at binfer :censored:



:smartass:

May be an old thread, fellas, but it's a similar problem. Give him some slack, eh.