Hi guys, been trying to work some stuff out with the bike, the idle fluctuates a bit and I seem to get harsh vibrations, noticeable more on the throttle side of the bars, also when trying to hold speed at about 70+ the bike is hunting a bit.

I’ve just done a service and checked tb sync and they are okay.
I’ve also recently unplugged the O2 sensor and fitted a pcIII with a map for my current mods, I think it’s helped a bit with hunting problem but the vibrations and idle problem are still there.

While running the bike up to temp I’ve noticed that the right side exhaust is noticeable hotter than the left, I can feel air coming out of both but one is warmer than the other, also the left Is almost cold to touch and the right isn’t. I know there is a join in the middle so assumed they shared the flow. Is one side being hotter a problem and could this be a cause/something that stems from my other problems?

Any help is greatly appreciated.

I’ve also just changed the spark plugs with the service, these are the old ones.

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Check charging voltage and even if ok,inspect magneto rotor magnets.
Here on the site you will find topics wit pictures an full description about the rotor.
Improper charging can upset spark,fuel injection.
Unbalanced rotor can cause excessive vibes.
Others might have more ideeas about the symptoms you have.
The left exhaust tube is longer than the other one(always cooler a bit),but this does not mean that has to be just warm to touch when the bike is at normal running temp.
Hope this helps!

I would be looking at how hot the header pipes are, not the mufflers.....although, they should be as hot as each other....

If you have a cold/cool header, then either you have no spark or fuel (coil / plug / injector) issue(s)

Those plugs are toast for sure, and one seems wet with oil, even up on to the body.....have you got oil weeping down into the spark plug well
one of them ? This can cause a direct arc to the cylinder head from the plug cap, meaning loss of spark in the cylinder....
If so, get the rocker cover off, and apply some gasket sealant and refit, then wash the plug bore out with brake cleaner or similar.
While you are at it, remove the plug boots from the leads and trim 3- 5mm from the leads and refit the caps to give a better contact.

If this isn't the fix, then maybe its a coil.....not common though.

Also, try swapping injectors over from one cylinder to the other, if the problem shifts, then thats a tell.....

Now, i have never worked on an O2 sensor system before, but, if the problem started after this work, i would reverse it and see if the problem goes away...then its possibly a mapping issue
or even a wiring issue..... schmidt314 will have something to offer on this one for sure

Thanks for the info guys really helpful! I’ve got some free time next week so I’ll look into the solutions you’ve given me and I’ll let you guys know if anything has worked 🤙🏻

One, i am interested to know if you got this sorted....


Two......i am also writing this as an excuse to see something, anything, posted on the site......where the hell is everyone...? HA HA....havent seen anything posted for many days now....