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Discussion Starter #1 (Edited)
Surging problem. Help!

Haven't had alot of saddle time on my RC so still learning to ride the bike. Maybe it's just me, but the bike refuses to run smoothly and surges badly at a steady throttle between 3000 and 3500 rpm. Above that it smooths out and runs strong. Bike came with Jardine RT-1 cans. Tailpipes are black but not sooty, so proably running rich. No Power Commander (nor do I know if fueling was ever remapped for the Jardines). Adjusted throttle cable free-play and throttle response is crisp. Starts easy and idles normally at 1300 rpm. Love the bike but the surging makes riding in city traffic a PITA. On the open road she runs awesome. Can a good Honda dealer run a diagnostic and/or remap the fueling (assuming that's the problem)? Throttle bodies out of sync? Injectors dirty? Bad fuel? Never riden another RC so have no comparison, but can't believe this is normal. Opinions? Thanks.

Doug
 

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Can you better describe the surging behavior?

I know my '02 does not like to putt in traffic below 3500 RPM.
The combination of large throttle bodies with barely cracked butterflies combined with on/off fuel injection can get into a lurching behavior.
I usually clutch it then smoothly reengage to stop that.
Once the throttles are open a bit more or the revs get up to 4000, no problem.

If it was a horse, I'd say it was chomping at the bits.
It just wants to be turned loose to run.
 

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Discussion Starter #3 (Edited)
Can you better describe the surging behavior?

I know my '02 does not like to putt in traffic below 3500 RPM.
The combination of large throttle bodies with barely cracked butterflies combined with on/off fuel injection can get into a lurching behavior.
I usually clutch it then smoothly reengage to stop that.
Once the throttles are open a bit more or the revs get up to 4000, no problem.

If it was a horse, I'd say it was chomping at the bits.
It just wants to be turned loose to run.
Hmmmm, no real need to describe the surging behavior any further as I think you just described the exact same symptoms I'm currently experiencing. What you said makes perfect sense - the big gulping throttle bodies mixed with trying to modulate small throttle openings creates a lurching sensation. And yes, I'm clutching it too, just to smooth out things untill I can build a few revs. By 3500 things are barely borderline and by 4k everything is smooth and all is well in the world. "Chomping at the bit" describes the behavior perfectly. This is my first V-twn so the learning curve is a distictly different one from my previous horses (2 VFR's, Triumph Sprint ST, and the silky smooth CBR1100XX). Must be the nature of the beast - thanks for easing my mental suffering.

Doug
 

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Change your gearing. Mine was like that till I changed it 15/42 seemed to make city riding better.
 

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Discussion Starter #5
Change your gearing. Mine was like that till I changed it 15/42 seemed to make city riding better.
One thing I forgot to mention is that the previous owner had put a 44 tooth rear sprocket on the bike. 44 seems awfully low gearing but I'm assuming he left the front sprocket stock which gives a 16/44 ratio. Don't know how that equates to the 15/42 most RC owners recommend. My bike pulls strong out of the corners and runs great on the open road, but it seems to be reving a little high at interstate speeds. I also think my speedometer is reading wildely optimistic, maybe 12 to 15% high. Gonna check my readings against a GPS this weekend. May have to spring for one of those SpeedoHealers.
 

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One thing I forgot to mention is that the previous owner had put a 44 tooth rear sprocket on the bike. 44 seems awfully low gearing but I'm assuming he left the front sprocket stock which gives a 16/44 ratio. Don't know how that equates to the 15/42 most RC owners recommend. My bike pulls strong out of the corners and runs great on the open road, but it seems to be reving a little high at interstate speeds. I also think my speedometer is reading wildely optimistic, maybe 12 to 15% high. Gonna check my readings against a GPS this weekend. May have to spring for one of those SpeedoHealers.
It sounds like the gearing is still very close to the 15/42, so no need to make a change there. As for the lurching, it seems to be common on this, and a few other larg liter bike's. My Hayabusa does the same thing, those not quite as rough as my RC. Crusing at low speeds (under 35), in any gear other than 1st, and both my RC and Busa lurch. I feel it mostly when I am going through a school zone (which are 20mph).
 

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Feel your pain oldgeezer, but thats not a city bike. I don't think that can be dialed out. Any rpm over 4k should work. The standard advice about gearing set up does help though. Get a fuel mapping device installed anyway. You will have a better response.
 

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Just picked up an '04 RC, and have been riding it for a couple of weeks now. I have the exact same performance - seems to be a bit choppy around 3k rpms. I find myself doing just what subsailor does - when needed, I'll clutch in and reengage or even change gears depending. I read up a lot on these bikes before buying mine, so I was expecting some choppiness. Sure enough, it takes some getting used to, but once you get some speed up, it's all worth it! My bike is completely stock, and I'd like to keep it that way, so it's something I'll have to get used to!
 

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Discussion Starter #9
Just picked up an '04 RC, and have been riding it for a couple of weeks now. I have the exact same performance - seems to be a bit choppy around 3k rpms. I find myself doing just what subsailor does - when needed, I'll clutch in and reengage or even change gears depending. I read up a lot on these bikes before buying mine, so I was expecting some choppiness. Sure enough, it takes some getting used to, but once you get some speed up, it's all worth it! My bike is completely stock, and I'd like to keep it that way, so it's something I'll have to get used to!
I've only ridden mine about 5 times now, so I'm still learning the bike. Very different from any of my previous bikes, plus it's my first V-twin. Was able to get in a 200+ mile ride Saturday morning, and little by little I'm developing a feel for the bike. And as you said, out on the open road, she's sweet. I've just about learned how to ride it at slower speeds - clutch it if necessary, but about the only guarantee for eliminating the lurching is to maintain a steady throttle around 4000 rpm. It's rideable down to about 3500, but it's much smoother if you can keep it above that. At anything below 3500 and down to 3000, it's almost impossible to maintain smoothness without clutching it.
 

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Hi, I've owned my '04 for the last 253 miles and it's got stock 16/40 gearing and lurches while riding in town. I've found that if I can hold the throttle at a point where the bike is making power to move I'm fine. If I'm coasting, though, and trying to crack the throttle enough to keep from using the clutch it'll start to lurch until I either A) clutch it or B) accelerate.

It's still very early in my ownership to decide on a gearing change, but I haven't even used 6th gear yet on the interstate. Hell, I barely use 4th around town! But I did my first mileage check on fuel last week and I got 43.5 MPG with it, and I'd HATE to lose that (I use the bike to commute).
 

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Discussion Starter #11 (Edited)
Corsair, the previous owner of my '06 did a radical gearing change by installing a 44 tooth rear sprocket, but my bike is still a PITA to ride around town. I have to hold a steady throttle of at least 4k rpm to maintain smoothness, and then it's noisy as hell in the city (bike has Jardines). Like you, I use my bike to commute (60 miles daily -70% freeway, 30% rural mountain road) so I would love improved gas mileage like you're getting. I actually installed a new OEM stock 40 tooth rear sprocket to achieve that, but discovered the existing chain was way too long for the stock sprocket (Now I gotta buy a new OEM chain). My bike turns about 4500 rpm at 65 mph in 6th gear. Standing start and roll-on acceleration is great, but gas mileage sucks. I've owned ALOT of different bikes, and I love my RC, but it's by far the most difficult bike to ride in city traffic. I know it was designed as a race platform, not urban commuter, so I guess we can't have our cake and eat it too. Should have kept the VFR for commuter duty, but can't afford the luxury of owning multiple bikes.
 

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Oldgeezer,
I have had my 04 since 06 when I bought it new in the create. I have had the same problem but it does not seem as bad when I went from stock to 16/42. I have SATO pipes and PC3 with a Dan Kyle map and a Turnone snorkel, K&N filters with the foam inserts.
I use it for my daily rider which is 40% highway and 60% Urban driving. The lurging you will get use to and pull the clutch in to slow it down LOL. My average fuel mileage with all the mods is about 120-130 miles per tank.
My biggest concern now is the overheating while cruising the small lakes in my area. The slow speeds and lack of fuel drives the temps up. I am looking at installing the Carbon fiber radiator air scoops but need to save a little more for the mod.
Hope you enjoy your SP2 as I will say I'm 51 and will never let her go :)
 

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Discussion Starter #13 (Edited)
Thanks for the tips, I'm still learning the characteristics of the bike, and now can control the low speed surging alot better. I'm getting about the same mileage as you, 110-130 miles before the reserve light comes on, depending on how and where I ride. Those mileage readings are probably optimistic, however, since my bike came with a 44 tooth rear sprocket (I'm assuming front is stock). I eventually plan on regearing to 16/42 like yours. Except for the Jardine slip-ons, everything else is stock to my knowledge (I can hear the servo/flappers kicking on and off). The biggest single improvement I've made in the bike was in resetting all the suspension settings per the owner's manual. Maybe not the optimum settings, but handling dramatically - she now turns in SO much easier, holds a perfect line through the curves, and the ride is more compliant on rough roads. The previous owner had the settings all screwed up - max preload at front and rear with compression/rebound settings all over the map. The bike was a pig to turn in and ran wide exiting corners, but now all that nasty handling is gone and the bike's a joy to ride. With standard settings as a base line, hopefully I can fine tune the suspension even better. I understand a Dan Kyle shock link also improves handling. Regarding other mods, I've heard about the PAIR and snorkel modifications but really don't understand how to do them. Guess I need to search out those mods elsewhere in the forum, as I'm sure they're covered here somewhere. Hey, I'm 67, so don't feel bad about being 51! The wife says I should get a cruiser, but where's the fun in that? No thanks.
 

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I have the turnone carbon fiber snorkle and it has really let her breath tie that with Sato low mounts and K&N filters she has not problem breathing LOL. I have not done the Pair mod only because of the emissions and where I ride. I am hoping to ride her to Knoxville later this year. I might try to stop in and say hi if I am close.
Keep the rubber side down and enjoy the ride as I know I do everyday with my 04 :)

GF thinks I need to grow up but I never will LOL
 

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Oldgeezer - that's great that you reset your suspension settings - I've thought of that, but haven't had a baseline to work from yet. I may tackle that next!

I have an '87 Hurricane in fantastic shape, but to be honest, I haven't ridden it since I picked up my RC about a month or so ago. Well, I got the old bike out this weekend to run a little gas through it, and was amazed at how smooth it was compared to the RC - the hesitation is so much more pronounced with the new bike. But, to be honest, I just didn't like riding the old bike much at all - and trust me - the hurricane is a great riding bike. I'll take the sore wrists and the jerkiness of the RC any day! Looks like I'm going to be putting the old bike up for sale soon. I have little time to ride, and any chance I get I'll be on the RC!
 
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