Leovince slip on

[cfar]

I noticed while watching a clip of the LeoVince that the owner revved a cold engine and as the revs fell back down again, it went a bit too far so as to almost stall. The bike recovered, then went on idling normally.

I haven't experienced this with the stock can, can anyone with an aftermarket slip on attest to this weird behavior?

Thanks,
Chris

 

[gpd211]

I ordered my Leo Vince the day I picked up the bike. So it has been on for most of the time I've had the bike. I don't rev a cold engine (let it warm up at idle) and have never noticed the idle drop below the 1100 Honda states as normal

 

[adger]

I've been running an LV slip on for a little over a month now. Started with the baffle in, now it's out. Sounds great. I've had no issues at all with any idle weirdness. The fit and finish of the silencer is excellent - great fasteners. Would definitely recommend it!

 

[2wheelcager]

Is there a bracket on the bottom of the Leo Vince for the center stand to rest on?

edit: I just found one post where someone claims it does. I'm surprised more people don't comment on aftermarket exhausts and possible center stand issues since it is such a popular and convenient accessory. Also ECU's do not lean out a mixture on cold start up, they enrich like a choke. Cold engines do need a richer mixture which promotes faster warm-up.

 

[Angry Outcast]

Pretty much any modern bike will do this when cold with a slip on. The engine is leaned out by the ECU when cold to promote a faster warm up, that combined with the slip on leaning the bike out a small amount can create a difficult running condition when the bike is revved. It is never good to rev any cold engine for that matter but even worse when they have a more open exhaust with no tune. Hope this helps answer your question.

 

[Bubba Satori]

Pretty much any modern bike will do this when cold with a slip on. The engine is leaned out by the ECU when cold to promote a faster warm up, that combined with the slip on leaning the bike out a small amount can create a difficult running condition when the bike is revved. It is never good to rev any cold engine for that matter but even worse when they have a more open exhaust with no tune. Hope this helps answer your question.

Here ya go.

 

[Spaceteach]

I'm guessing that the slip on had nothing to do with the momentary drop in idle speed on the video. LeoVince claims their slip on is designed to work with the stock fuel management system on this bike and the NC uses a closed loop fuel management system with an exhaust oxygen sensor. The ECU should maintain the same mixture regardless of exhaust unless the slip on makes a big enough change to go beyond the range of the sensor. I think it's far more likely that it took a moment or two for the ECU to compensate for revving the cold engine under no load.
Angry Outcast, I don't think I understand what you posted about the ECU leaning out the mixture on a cold engine. I know modern ECUs lean the mixture as soon as possible as a cold engine warms up, but I had always thought that cold engines needed a richer mixture. Kinda the reason carbs have chokes.

I could well be wrong (and probably am) but that's my story and im sticking to it,
Bob

 

[adger]

Is there a bracket on the bottom of the Leo Vince for the center stand to rest on?

edit: I just found one post where someone claims it does. I'm surprised more people don't comment on aftermarket exhausts and possible center stand issues since it is such a popular and convenient accessory. Also ECU's do not lean out a mixture on cold start up, they enrich like a choke. Cold engines do need a richer mixture which promotes faster warm-up.

I can verify for sure that it does have the center stand rest. I put the center stand on about 2 weeks ago, and it meets up perfectly.

 

[LA_NC700X]

I can verify for sure that it does have the center stand rest. I put the center stand on about 2 weeks ago, and it meets up perfectly.

LV has a few version of pipes... Which one do you have? Slip on, correct?

I bought one of those cheap china pipe and I have to end up taking it off when I put in my center stand...

 

[Angry Outcast]

I'm guessing that the slip on had nothing to do with the momentary drop in idle speed on the video. LeoVince claims their slip on is designed to work with the stock fuel management system on this bike and the NC uses a closed loop fuel management system with an exhaust oxygen sensor. The ECU should maintain the same mixture regardless of exhaust unless the slip on makes a big enough change to go beyond the range of the sensor. I think it's far more likely that it took a moment or two for the ECU to compensate for revving the cold engine under no load.
Angry Outcast, I don't think I understand what you posted about the ECU leaning out the mixture on a cold engine. I know modern ECUs lean the mixture as soon as possible as a cold engine warms up, but I had always thought that cold engines needed a richer mixture. Kinda the reason carbs have chokes.

I could well be wrong (and probably am) but that's my story and im sticking to it,
Bob

The reason carbs have a choke is they do not atomize fuel like injectors do. With "globs" of fuel and cold air it makes it harder for the spark plugs to ignite the fire. The better atomized spray from injectors makes the fuel far easier to ignite. At first crank they do get a good dose of fuel but once started it slightly leans the mix to accelerate cylinder heating to help the engine warm up faster. Thats the most condensed version I can give. Also when I say leans the mix, it is very minimal, too much and you melt a hole in a piston. Thats just not good for anyone. More fuel results in a "cooling" effect, thats why when I built drag cars I would run alcohol in them instead of gasoline. You ran 40% more alchy than gas by the combustible nature of liquid corn giving off less energy but in return the engines ran cooler so we could run higher compression to build more power. Plus its cheaper than race gas.

 

[adger]

LV has a few version of pipes... Which one do you have? Slip on, correct?

I bought one of those cheap china pipe and I have to end up taking it off when I put in my center stand...

Bummer. Well the one I'm running is specifically this one. LV ONE Evo II, in stainless steel. I mentioned it in another thread, but I went with SS over carbon fiber - the carbon fiber pipes have a limited lifespan due to eventual fatigue cracking.