Hello!

I bought a 2012 1000rr. I have liked the bike very much but there is one problem that is driving me crazy: When im cruising in the city 3rd-4th gear and 2500-3000rpm range the bike is very jerky and bumby and it feels like the whole bike is jumping a little. It feels like the back end is making a push-pull-push motion but this goes away if I give it some gas and get the bike over 3000rpm. This problem seems to be active on all gears when im staying in the ~2800rpm area.

The chain and sprockets seems to be ok and the chainslack is within specs. The chain adjuster is in the "replace" chain area but it doesent really seem worn. Previous owner has changed hiflow airfilter and Acrapovic slip on to the bike but no powercommander etc. I have read a lot about the flat spot on that rpm range and I was thinking that maybe the engine is not running smooth because of these changes and that makes it so jerky at those rpms. Does that make any sense or could it just be the chain?

Anybody having the same kind of problems?

Thanks!

 

What is the condition of the Damper Set parts of the rear hub. Ove the years they tend to get hard and fall apart.

Item #1 on this page.

https://www.partzilla.com/catalog/ho...0rr/rear-wheel

 

Thank you for the reply!

I was thinking about this part too. My chain and sprockets will be done friday so I will inspect this part at the same time if possible. Hopefully the problem is one of these parts but im not very optimistic about it. There is also some kind of hesitation in the power delivery at those rpm ranges which goes away when I go over 3000rpm.

 

Once you have the wheel off the bike, the sprocket and hub come right off the wheel. Easy to check them over.

 

If it is not the Damper Set or (Cush drive as I know them), it is likely to be the fueling. As you have suggested it is quite common for hesitation at around that rev range where to aid emissions checks they are set to run quite lean, which will have been exacerbated by the air filter / can combination.
I have the same mods done on my F4i and had a PC fitted and mapped which eliminated that dead spot and smoother out the lower end power delivery considerably.

 

Yes, now im pretty sure it is a fueling problem. Chain and sprockets was changed today and the Damper Set / Cush drive was inspected by the mechanic which was in good condition. It helped to smooth the bike a little but the problem stays the same in that rpm range.

So I need to do something about the fuelling. I dont know how long its been used with the slip on but hopefully it has not damaged the engine or valves. I guess the choices are PC or flashing ECU. I havent heard much good things about the powercommanders so I guess I would personally prefer the ECU flash. I dont know which one is more expensive and are there anybody who can do it in my city.

 

There is nearly Zero chance that having the Slip-On exhaust on your bike has caused any damage to the engine, valves or otherwise. You would need to replace the exhaust headers before you're going to notice any change in performance. Air filter and slip-on isn't going to do it. How much slack do you have in your throttle cable? Maybe adjusting that so you have better control over that might help.

 

Thats good to know. The first thing i did was adjust the throttle cable slack to the right amount but it didnt really help with the problem. Maybe i will try to set it a bit tighter because there is some slack right now after I adjusted it.

 

Naturally you don't want it so tight that it starts binding up. But I suspect that the amount of slack the factory recommends might be a little on the loose side. I think I'd try to get it as close to zero slack as I could and still have it moving freely and it always returning to full off if you let it go while riding. Make sure you test throttle movement with your handlebars in full left and right lock position to be sure.