Engine Hesitation

[gazzzwp]

Hi all

This is not a serious problem but nonetheless one I would like to solve. There is some hesitation around 2500rpm to 3000rpm that feels like an HT or fuelling problem.

When accelerating even very lightly the problem is hardly noticeable. To notice it you have to virtually hold the revs constant at the flat spot and then you feel the hesitation. As soon as a minute amount of power is applied the problem goes.

Otherwise it's fine through the rev range from low down below 2500rpm to cruising at 5000rpm or higher.

Quite puzzled about this. She's done 6100 miles, and is 3 years old. The plugs were changed last year at 5000 miles. The air filter has not been changed and I plan to do it next year. In my experience this tends not to make a huge difference to the engine but I'm open to suggestions.

I have sprayed the plug tops and HT leads in case there is some leakage. No trace of HT leakage anywhere and I would have thought that this would have given problems through the entire rev range.

There it is guys - open to suggestions please.

G

 

[charlie b]

Three things to check.

1. Is you bike on the maintenance bulletin list for plug cables/caps. There were some that had issues and needed to be replaced.

2. Mine did exactly the same thing. It turned out to be one of the fuel injector electrical connectors had popped loose.

3. Bad plug(s). At 8k mile service you are supposed to replace the plugs, so, you might be experiencing an early failure. (sorry, I see you did this early)

 

[gazzzwp]

The injector plugs sounds a likely candidate. How much of a strip down would this entail? Presumably side panels, fairing pockets, lift up tank and remove air filter box?

I have not had notification from Honda regarding the plug caps - how would I know if my model was affected? I will Google it first.

 

[charlie b]

I have no idea. Mine was under warranty so I wheeled it into the dealer. I asked them about the plug wire/cap issue and mine was not on the list (ABS, ser no ...00028). They found the FI cap issue and sent a note to Honda USA about it. FWIW, it took them three test rides to figure out the problem. At first they blamed bad fuel. Then decided it was just a twitchy throttle and an inexperienced rider (me). Then the third ride they finally admitted it was an issue.

 

[Chuck 500]

There was no recall on the spark plug caps. I was a service buletin for dealers to check when bikes came in for service or reported the problem. I inquired and my was not on the list. It's worth checking.

Chuck

 

[Phil Tarman]

IIRC, there wasn't a "list." It seems to me that the service bulleting said that if a bike exhibited the symptoms, replace the caps. The caps aren't very much (seems like under $5 apiece) if your dealer doesn't want to do it and you do. I'd be guessing injectors, but I really don't know much about fuel injection. It's sure not anything I've ever felt.

The service bulletin might have just listed 2010 bikes, too.

 

[charlie b]

The service bulletin says to check the caps. If they are a specific brand then they are OK. If not then they should be replaced. At least that's the way I read it (and so did my service manager). Mine were OK from the factory.

The hesitation/miss the OP is experiencing sounds exactly like the problem I had with mine. Acceleration great. Deceleration fine. Hold a steady 35-40mph and it would stumble and sometimes just plain quit. It was hard to notice at first because any throttle movement and it would not happen. That's why the service folks did not believe it had a problem when I first took it in.

 

[gazzzwp]

Thanks guys - what I will do is strip it down to remove the air filter box - the injector plugs should be visible from there. While I'm at it change the plug caps and air filter. Do the whole lot at once.

Regarding plug caps; do they literally just screw off and screw in?

 

[bicyclist]

Regarding plug caps; do they literally just screw off and screw in?

Yup, when you look at the new ones, you'll see what looks like a brass wood screw in the cap. Just twist it on. The cap will come with two rubber boots to seal it to the wire at one end and the sparkplug at the other. You may need to hold the wire with pliers to twist off the original cap, it's on pretty tight.

 

[gazzzwp]

Looks like the problem is solved!

The new NGK plug caps arrived today - thanks to the person who found the ebay link to the correct parts!

I promptly set about fitting them as it was a very easy job. I noticed that on the LHS the HT lead virtually fell off the plug top when I unscrewed it. It was loose and this could well have been the source of the problem. On the RHS it was necessary to thread the plug cap over the frame section first in order to get more cable to play about with. The HT lead on this side was on nice and tight.

Both new plug caps went on ok and after taking her for a ride it looks very much as if the problem is cured.

Incidentally one of the injector plugs is visible and just about accessible with the side panel removed. It looked to be on ok and so I don't think I will bother stripping it down to check the other injector for now.

Thanks for al the good advice.

Cya all soon

Gary

 

[elizilla]

Glad the plug cap thing helped you!

AFAIK, the plug cap bulletin was USA only - the UK forum hadn't been aware of anything from Honda about it though some had found the issue on their own. I posted a link to the copy of the USA version of the bulletin in one of the other threads out here.

Also, I wouldn't put much stock in a dealer looking up your bike in their computer and saying you don't need new plug caps. My dealer looked mine up and said I had the correct plug caps, but when I checked them myself according to the directions in the bulletin, it had the ones the bulletin says are bad.

 

[mat0000]

Hi,
I have exactly the same problem. Can anybody tell me where I can find the spark plug caps on the internet?. Thanks.

 

[elizilla]

I ordered them from Amazon.com. See this thread, several pages in.... http://www.nt-owners.org/forums/showthread.php?850-Engine-rough-idling-when-stopped

 

[gazzzwp]

As a matter of interest the part number on the old plug caps I removed is:

TP05K02W

The manufacturer is a little hard to discern but it looks like 'TEL'.

Any thoughts comments?

G

 

[Cochise]

Hey guys. Just wanted to post an update on those pesky original spark plug caps. My 2010 NT700V with ABS started cutting out/hesitating at slow speeds after about 30 minutes of riding. It would idle very rough and then die. It would run OK if you kept the rpms up, but hesitated from a standing stop which can be dangerous on a bike. I suspected the plugs might be the problem, but honestly didn't want to take off all the plastic to get to them. I replaced the plugs about six months ago, and it was the hardest plug replacement I've ever done.

Anyway, I took the bike to the local Honda dealer, Hall's Motorsports in Daphne, AL to have them diagnose and fix the problem. They kept the bike for three weeks. I had to call them to find out what was going on. I spoke to the service manager, who said he would call me back with details. He didn't call so I eventually went to the shop on my own. He told me the mechanic diagnosed the problem as a potentially blown head gasket. Said he heard a hissing noise coming from the front cylinder and smelled coolant. Wanted my permission to tear it down and run some extensive diagnostic tests. He said the oil looked good (often coolant will get into the crankcase with a blown head gasket). I asked him to check the coolant level and he said it was low normal. I found it hard to believe the head gasket had blown with only 14,000 on a lightly ridden bike and no telltale symptoms. I said nope, don't worry about tearing it down further. That would have cost hundreds, and a blown head gasket repair would top a thousand easy. I took it home, ordered a new set of spark plug caps through partzilla.com 30700-MEW-922 CAP ASSY. (Honda) $11.14 ea. Tore off the plastic, installed them, and the bike runs like a charm.

I suspect the dealership, who I've had lackadaisical service from before, either wanted to run up the bill by unnecessary diagnostics or the mechanic didn't want to fool with it so he diagnosed it with a really expensive problem so I probably wouldn't pursue it. Problem is, Hall's Motorsports is a chain all over the Southeast and it is hard to find a Honda dealership that is not a Hall's clone. Next time I need dealership work, I'll take it to my Triumph dealer in Pensacola, D&D Cycles, who do good work on my 2006 Triumph America.

 

[seagrass]

Thanks for the update. It is easy to see why a lot of us do our own repair work and why we have trouble trusting dealers to diagnose problems.

Forums like this one are great tools to help with diagnosing problems as we all own the same motorcycle and therefore the combined knowledge about the NT700 is probably much greater than many dealers (especially dealers who rarely or never work on NT700’s).

Good to hear you got the problem solved.

Seagrass

 

[Brillot2000]

Issues similar to this are either ignition or fuel related. The symptoms are sometimes misleading too.

When was the last time spark plugs were changed, if not at all? Start with the plugs and then the plug caps.

On the fuel side, things can get expensive quickly. The fuel filter is integrated into the pump assembly, which is about $400.

If the bike sat for a long time, you may want to take a look at the fuel cap vent for proper operation as well. Its cheap check and take a moment to verify.

 

[Phil Tarman]

Fuel pump plus a couple hours of other work cost me about $700. After 130K miles, that wasn't too bad.

 

[stephensatt]

Hey guys. Just wanted to post an update on those pesky original spark plug caps. My 2010 NT700V with ABS started cutting out/hesitating at slow speeds after about 30 minutes of riding. It would idle very rough and then die. It would run OK if you kept the rpms up, but hesitated from a standing stop which can be dangerous on a bike. I suspected the plugs might be the problem, but honestly didn't want to take off all the plastic to get to them. I replaced the plugs about six months ago, and it was the hardest plug replacement I've ever done.

Anyway, I took the bike to the local Honda dealer, Hall's Motorsports in Daphne, AL to have them diagnose and fix the problem. They kept the bike for three weeks. I had to call them to find out what was going on. I spoke to the service manager, who said he would call me back with details. He didn't call so I eventually went to the shop on my own. He told me the mechanic diagnosed the problem as a potentially blown head gasket. Said he heard a hissing noise coming from the front cylinder and smelled coolant. Wanted my permission to tear it down and run some extensive diagnostic tests. He said the oil looked good (often coolant will get into the crankcase with a blown head gasket). I asked him to check the coolant level and he said it was low normal. I found it hard to believe the head gasket had blown with only 14,000 on a lightly ridden bike and no telltale symptoms. I said nope, don't worry about tearing it down further. That would have cost hundreds, and a blown head gasket repair would top a thousand easy. I took it home, ordered a new set of spark plug caps through partzilla.com 30700-MEW-922 CAP ASSY. (Honda) $11.14 ea. Tore off the plastic, installed them, and the bike runs like a charm.

I suspect the dealership, who I've had lackadaisical service from before, either wanted to run up the bill by unnecessary diagnostics or the mechanic didn't want to fool with it so he diagnosed it with a really expensive problem so I probably wouldn't pursue it. Problem is, Hall's Motorsports is a chain all over the Southeast and it is hard to find a Honda dealership that is not a Hall's clone. Next time I need dealership work, I'll take it to my Triumph dealer in Pensacola, D&D Cycles, who do good work on my 2006 Triumph America.

Sorry to be late to the punch by my 2010 NT700V is doing something similiar after sitting in garage un-used for 6 months ( I have other newer shinier bikes, sorry NT) . I did install new plugs, and have new gas in it, and I did test the ohm reading on the Pulse Generator last night and I got 550 ohms which is correct. I have just recently been reading about the spark plug caps being a recall item. Maybe thats what my problem is. I don't get an engine light but once the bike heats up it idles horribly and hesitates badly and dies sometimes when you give it gas. I have installed a new air filter, and bike only has 10k miles on it. I think I will go ahead and order those anyways because its cheap and I have the gas tank tilted up right now, and the air cleaner removed trying to figure out this issue.

Thanks for the write up.

 

[mikesim]

If it ran ok when put up but now runs poorly after being laid up for ~6 months, I would suspect a fueling issue. Even though you drained most of the old fuel out, you may have some residual gunk in the fuel injectors/throttle body. Try a dose of Seafoam, 2oz per gallon of fuel and take it for a long ride, and report back.

Mike