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Glitches when running at steady speeds/revs (on the road)

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Got a 03 CRF450R and while anyone riding a similar model CRF will most likley have seen my thread in the CRF450R section, maybe this is common to a lot of SM riders on bikes with FCR carbs?

In short, when I'm cruising at a steady speed on the road (say 30-50mph) and holding steady revs, the bike glitches a little every 1-4 seconds. Doesn't slow down as its over with in an instant, but its annoying. At first I thought maybe fuel starvation but ruled that out almost straight away as if I twist the throttle at any time, the bike leaps forward as its designed to be so it can't be lacking fuel in the bowl and the carb is spotless.

Any ideas? Anyone experienced similar even on a different make of SM to a Honda?

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Got a 03 CRF450R and while anyone riding a similar model CRF will most likley have seen my thread in the CRF450R section, maybe this is common to a lot of SM riders on bikes with FCR carbs?

In short, when I'm cruising at a steady speed on the road (say 30-50mph) and holding steady revs, the bike glitches a little every 1-4 seconds. Doesn't slow down as its over with in an instant, but its annoying. At first I thought maybe fuel starvation but ruled that out almost straight away as if I twist the throttle at any time, the bike leaps forward as its designed to be so it can't be lacking fuel in the bowl and the carb is spotless.

Any ideas? Anyone experienced similar even on a different make of SM to a Honda?

My bike is an '06 XR650L with a 41mm FCR and it does the same thing. I just ignore it and crank the pizz out of it. Maybe there's a remedy, but I figure ... what the hell, it's 10,000X better than the stock carb (and Eddy pumper), so I can live with it. :thumbsup:

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I my WR you can tell when its switching ignition maps during certain light loads, so I just downshift and run a higher rpm. Other wise when I'm on the throttle it's wonderful!

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Sounds promising in that Im getting the feeling this might be fairly common although not sure about the switching off ignition maps on mine as the last run out I disconnected the TPS to rule that out which according to sources on here means the bike resorts to a 2D map without ignition advance (and/or retard) and so shouldn't be switching but the glitches were still there.

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check the valves. my wr does it too and shop told me it needs a valve adjustment or check.

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My valves are good, common occurrence. It's what happens when cruising on a race bike.

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I put a std 170 jet on the bike at the weekend as it had been running a 185 for some reason even though the motor is fairly stock and it does seem to have helped a little bit in that its still there but not quite as bad as before. The main plus with the 170 is the bike feels even better on the gas than before.

As my valves are in spec, I'm going to put the glitch down to what a few have suggested with it being a symptom of flat side carbs :banana:

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