Sounds like a chain rattle

Good evening all.

I'm afraid I'm new to the st1300 experience, and for the most part I'm loving it. Now that being said I'm noticing a persistent noise from the engine. It sounds like I have a loose chain (and yes I'm aware it's shaft drive hence the concern).

A little background if I may. My bike is a 2005 st1300 with 54000km on it. I've only had it for a few weeks but I've put on almost 2000km (smooth, and exciting kilometres). As soon as I got this bike I changed her oil and put in synthetic, filed the tank with premium gas, and rode for a couple of hours. Now when I'm getting out of the hole and not pushing her I got the rattle until about 3000rpm. Now it seems that unless I'm cruising at alreast 3300rpm the rattle persists. When I'm rising 2 up its constant regardless of the tach.

I'm concerned that this could be a sign of something serious and I'd like to address it before it causes any real damage. Any and all thoughts would be greatly appreciated.

Neil

U joint ??

Check those reports and fix threads.

ToddC

HRH Neil said:

Now when I'm getting out of the hole and not pushing her I got the rattle until about 3000rpm. Now it seems that unless I'm cruising at alreast 3300rpm the rattle persists. When I'm rising 2 up its constant regardless of the tach.

Click to expand...

The engine in the ST (either of them) is nothing like the twin in the Suzuki you mention in your intro and can't be run the same way. This comes of frequently with riders who come from cruisers, and I went through a bit of it myself.

Read this thread, especially post 20 and make some adjustments to your riding. You'll find that the machine is a different beast when you're not [-]lugging the engine[/-] asking the engine to make torque where it doesn't.

--Mar

Might your 'rattling' be detonation? Aka 'pinging'? This is when you open the throttle wide and the bike is lugging along not putting out enough torque - or the octane rating is too low. Mark's other explanation for what you are hearing might be right on the money, though I tend to keep my rpms low, and am very careful not to lug the engine or ask more than it can comfortably crank out. And yes, I do downshift a lot to accelerate to pass someone (evidence I might be riding in too high a gear).

Pretty much the only other thing that can rattle is the balancer..it can either whine or rattle if not adjusted properly.There's a thread on here for addressing that issue....good luck.........ff

Looks like I have to get my head around the fact that she's a sport touring bike and not the cruiser that I've been used too. That thread about riding at higher rpms makes me feel better about leaving it in the 3500 to 4000 range. All the fun without the guilt, what could be better....

Neil, if you can capture an audio clip of the sound, that would be better than our guessing or assuming the cause. Or if you can confirm you whack open the throttle at 1000 to ~3000 rpm, then yes, that can be an explanation (but doesn't prove) the noise being lugging.

Regarding 'lugging" ...

Just because the engine rpm may be 'lower' than optimal doesn't constitute lugging--but lugging can happen at low rpm when the rider asks it to produce a lot of power (which is better produced at higher rpm).

This motor design is smooth and quiet and it is able to accelerate gently, without engine grumble, at 'low' rpm. Should that be common practice? No, because the ST's engine really performs at 4000+ rpm, but low rpm alone isn't proof that the engine is lugging. To wit, see the owner's manual shift points to illustrate Honda recommends changing gears at point that require low rpm! I'm not advocating always running at lower rpm as higher rpm is better for maintaining oil thickness (not dragging metal against metal) in the bearing surfaces and to avoid buildups in the combustion chamber and exhaust valves. Rather, the point is just don't whack open the throttle at lower revs.