new RVF - has it got a flat spot??

[racingt]

Hi guys, bought low miles RVF yesterday. Bike looks stock, except for polished bits, mini indicators, carbon end can.
I don't know what a flat spot is, but it stutters around 5-6k, almost a misfire, but not a misfire. Once over 6 it runs smoothly, takes off like a train, but not as good as my other RVF which also has open can, but has shims under stock needles and jets.

So do I need to shim the new one, or have I got a slow running jet blocked or something similar?

Idle speed also 2k which seems high.

All advice appreciated, thanks

[Neosophist]

Turn the idle adjuster down?

Sounds like a flat spot to me. Raising the needles with a shim will richen up the area between 5-7k, which is where your bike is struggling.

[racingt]

Hi, thanks Neo, do I need a kit from RO, or is this a simple set of Halfords washers!
I guess it's the kit.....

[jay3]

You don't necessarily need a kit, just 4 very thin washers. I would give Rick a call, explain to him what is happening, he will sort you out. As he as done for me, on many occasions and I would assume many others on here too.

please don't get some washers from Halfords, or you will be back on here again asking why your bike is running terrible.

[racingt]

cheers guys, spoke to RO last night, very helpful, good advice which I will follow. Hope I don't break it....

[samace]

I had the same problem with an RVF i bought which had been laid up for five years. I stripped the carbs and ultrasonically cleaned them and put it back. Still same, I then looked at jet sizes and was advised on here that 108 was ok for a standard RVF. But when first bought my NC30 10 years ago you need to change main jets from 110 all round to 115/118.This is well known on here and is in that excellent carb guide by Cammo. But no mention about changing RVF jets yet the bike is an import like my NC as I have both now. This had puzzled me so I then started to think and increased the jets to 112.5 which was better, I then tried 117.5 which they are now on and the problem has nearly gone but 80% better. If you made sure tap is ok and supplying enough fuel I would look at your jet sizes and if they are standard change them to at least 117.5 ( I would put 120 in myself). I have not yet tried the 120 jets yet as I have then will try them soon.

PS I tried the washers alone did not make much difference.