hesitation?

[pantstain]

04 xb12r....Anything below 3k rpms and motor has a slight hesitation when holding a constant speed...and very slight unless rpms are under 2k...then it's more noticable...and nothing past 3k seems fine or if your accelerating. Just purchased last week. Anyone able to point me in the proper direction? Or a few options to look at anyway. Thanks

 

[Theycallmecrash]

Your description is a bit confusing. When isnit ok and when does it act up?

 

[pantstain]

Sorry. ....it's fine at 3k and higher rpms....anything lower and it does that....The lower the rpms the more noticable it is

 

[Chicknstripn]

Does this happen in every gear or just first? I thought I had a fueling issue with my 07 xb12r until I isolated my symptoms to occurring only in 3rd gear. It was my transmission that was the problem, not my fueling.
Anyway, what else do you know about the bike? Have you changed the air filter? Does your fuel pump seem to be working fine? Does the bike have a stock ECM or race? Have you or anyone before you tried fooling with the fueling? Do you have a check engine light popping up when the bike sputters? Does the bike have a breather reroute? Could the reroute or the crank case breather be clogged? Your issue could be something as simple as plugs. Do you know when they were last changed? How many miles on the bike?
You see where I'm going with this? You can't give us too much info when you're trying to get diagnostic help on a forum.
BTW do yourself a favor and get the free version of ECMspy and a cable. At least with that you'll be able to get a better picture of what the engine is doing.

 

[pantstain]

It's every gear for sure, unfortunately the guy I bought it from didn't know much. Air cleaner looks pretty new...it's barely turning grey, fuel pump sounds ok, runs for a couple seconds and souns normal when priming...and sounds fine when bike is running, I haven't messed with the fueling...no idea what ecm it has or where to look to find it. No check engine light at all. Not sure if it has a breather reroute (just bought it a few days ago). Not sure on plugs either....16,100 miles on bike. Got a link where I can get the cable for ecmspy? I'll pick one up

 

[user_deleted]

cables and software CD available on ebay among other sites. i have owned 4 xb12 models between 03-07 model years and every single one of them was low mileage mint condition....and every single one of them had an incredibly annoying low rpm "lean" type surge. what worked for me and solved the problem was:
breather re-route
NGK DCPR9EIX plugs
clean air filter and filter base
clean IAT switch
a close examination of the plug wires and coil grounding point
clean injectors
"race map" installation that an ecm dim-wit such as myself was capable of doing
ecm on learn mode for a nice easy 25 mile ride
the above cured the stumbling and hesitation issue on every 12 i've owned. i would start there.

 

[pantstain]

Ok thanks fringe....are there any links to a breather reroute guide? Sry if i missed it...on my phone at work and doesn't work great on this site. And where can I find the IAT switch? I'm headed monday to my dad's to work on it and my car (3 hr drive)....he has been a mechanic his whole life and has rode bikes and worked on them his whole life as well. Just trying to get some heads up on what to look for when I get there.

 

[user_deleted]

remove air box cover....filter cover (6 snaps)...lay it aside after removing tank breather hose....remove air filter then air box base which is held onto frame/tank with 4 large stainless torx screws. look under base and you'll see small harness going to a sensor. that is the IAT switch. clean it with isopropyl alcohol or any other type of non-corrosive mild cleaner. be sure harness firmly reattached upon reassembly. tons of posts on here regarding breather re-route. when doing same be sure to plug the 2 large holes in air box base where the 2 factory breather tubes formerly resided. install your spark plugs while all the above is removed. front plug is done with 5/8th box wrench....rear plug with 5/8th insulated plug socket, 3/8th swivel, long 3/8th extension and 3/8th ratchet. these tools allow rear plug to be removed and installed without rotating motor. start plugs by hand and be gentle with them or you run the possibility of cross-threading the head threads.

 

[pantstain]

Ok cool. Thank you. Btw in case I didn't mention it the only thing I know for sure that's been done is a d&d slipon has been put on

 

[mrlogix]

the only thing I know for sure that's been done is a d&d slipon has been put on

"race map" installation that an ecm dim-wit such as myself was capable of doing

[up][up]

 

[pantstain]

Can you remap the stock ecm? Or do I have to replace it?

 

[go cytocis]

Can you remap the stock ecm? Or do I have to replace it?

Both.