[mzebley]

So I finished with my air flow upgrades this past weekend. Got the bike put back together and it fired right up...success! I'm loving the tone of the Leo Vince silencer; a nice fat growl, but not too loud.

Here are a few observations and questions I have:

1. Here's what came out of my carb. It appears to be a KLX needle kit! I hadn't expected this as I thought the bike was bone stock. When I purchased the bike two years ago (with ~1200mi on it) the dealer mentioned that they tuned the carb, but nothing about an aftermarket carb kit.

I also noticed this writing on the carb for the first time, and I can confirm that the main jet I removed was a 142 and the air/fuel mixture screw had been backed out 2.5 turns.

2. In addition to the new silencer, removing the snorkel, air box mods, I decided to go with the MCP carb kit. I must say that there doesn't seem to be a huge difference in low end torque from where the bike was previously. Because I thought I was upgrading from stock, I was expecting a more noticeable difference. The bike did "wake up" in the higher revs. From 4500 - 6500 RPMs the bike really pulls and the new silencer starts to scream and shout. That's just not my riding style. I typically tractor around, shifting around 4500 RPM. Well, like anything new, I'll have to spend some time getting used to it.

3. I'm very curious to see how this new set up does with fuel economy. I've been keeping records since I bought the bike and I am averaging 40.4 MPG. Compared to others on this forum, this is quite low. I was hoping that these mods might increase my fuel economy and save some fuel money over the long haul. I guess we'll see.

4. One thing that surprised me is that the new silencer gets really hot. My stock unit never got this hot. I tuned the carb according to instructions by NormK (which I found on this forum quite some time ago) and ended up 2.5 turns out again. Grant's instructions for the MCP kit offer a suggested range between 2.25 and 3.0 turns out, so I'm at least still within the parameters. I'm wondering if my tuning has anything to do with the heat of the silencer. Does anyone with Leo Vince have similar issues? Should I be worried abut the heat, or is this normal for aftermarket silencers?

5. I completely deleted the entire vacuum system, including all of the hoses and the valve. The MCP kit even comes with a small rubber plug you install instead of a tiny o ring underneath the air cut off valve on the side of the carb. I also installed a manual petcock conversion kit, which is essentially just a block off plate that replaces the vacuum valve on the back of the stock petcock. Now I have to get in the habit of turning the fuel valve off after each and every ride. Question: if I do forget and leave the petcock on, will it automatically flood the crankcase with fuel? I saw Tom's overflow vent mod, but since this was the first time I was into the carb I didn't want to do too much.

6. Lastly, I need to buy a set of JIS screw drivers.

Thanks for everyone's helpful feedback and comments here. I appreciate it!

Matt

 

[Six8five]

My Leo doesn’t get hot.
Other than the bogus website claims I’ve never heard of MCP kit getting better MPG.

 

[KLR-Mule]

I've been keeping records since I bought the bike and I am averaging 40.4 MPG. Compared to others on this forum, this is quite low.

That seems about right for a “jet kitted” carb.
It’ll take off ~5mpg in most instances.
For some, the additional power output is worth it!

Having said this, I opt for fuel mileage over performance. The KLR doesn’t…nor will it ever have any performance to begin with 😂
Having another 25-30 miles (per tank) is always appreciated on my longer riding trips.

 

[ptxyz]

i've left my manual fuel valve on and it will almost always be fine. if the rubber on the needle valve starts to deteriorate, it might not be...

i've comparable mpg with my klx needle and 142 main but, i'm abusing my poor klr on the freeway at 75+. i get 50'ish when i'm taking it easy.

my aftermarket laser exhaust gets hot but, not abnormally so. too bad we're all just guessing at that, it doesn't seem much different than the cans on any other of my bikes...

 

[banditcilik]

I assume the aftermarket can is hotter compared to the stock due to absence of the chicken crop part which also dissipates heat

 

[pdwestman]

1. Here's what came out of my carb. It appears to be a KLX needle kit! I hadn't expected this as I thought the bike was bone stock. When I purchased the bike two years ago (with ~1200mi on it) the dealer mentioned that they tuned the carb, but nothing about an aftermarket carb kit.

I also noticed this writing on the carb for the first time, and I can confirm that the main jet I removed was a 142 and the air/fuel mixture screw had been backed out 2.5 turns.

Too the well trained eye that Short Top Stem above the circlip on that mid-range needle suggests it was a DynoJet Kit.
Both the needle & the taller headed main jet are probably stamped "DJ xxx". Use a magnifier.

A Properly installed KLX jet kit would have had 1mm thick brass spacer installed on Top of the circlip to prevent the needle from 'floating' up & down under the white plastic needle retainer. The DJ needle should have had 3 thin shims stacked on top to do the same.
The KLX needle has a taller Stem above the circlip grooves to retain its spacer. (ID# N1TB)

The DJ main jets are Richer size for size than Keihin main jets. The Keihin main jets have a stylized 'K' near the size #.

Your bike was possibly running richer than necessary with that previous jetting set-up, reducing fuel mileage and causing the exhaust to run cooler.

 

[PeteK]

I documented more than15% fuel mileage loss at 65MPH by switching from stock to MCP. I did this testing back to back, on the same highway, at the same temps, over a measured 100-mile course. It did give a small increase in WOT performance, measured by the time accelerating WOT from 50-70-MPH. It did it about 1/2 second faster. Is that worth a 15+% loss in mileage to you? It wasn't to me. The KLX kit loses about 10% fuel mileage. .

 

[mzebley]

Thanks for everyone's comments. I'll try the MCP for awhile and see how I like it, as well as continue charting my fuel economy.

I kind of wish I had known that I had a carb kit already installed; I would have just started with the air box and silencer mods to see how that particular combination worked so I could have a direct comparison after installing the MCP kit.

That's a keen eye Paul. I've never seen a DJ kit before and so when I saw that smoother and more consistent needle tip, I just assumed it was a KLX kit.

I'll ride it for awhile and maybe swap back in the DJ kit just to compare.

One last question/verification: could my carb tuning be the cause of my overly hot Leo Vince? If so, how can I correct it? Is it too lean?

Matt

 

[MN Willie]

Thanks for everyone's comments. I'll try the MCP for awhile and see how I like it, as well as continue charting my fuel economy.

I kind of wish I had known that I had a carb kit already installed; I would have just started with the air box and silencer mods to see how that particular combination worked so I could have a direct comparison after installing the MCP kit.

That's a keen eye Paul. I've never seen a DJ kit before and so when I saw that smoother and more consistent needle tip, I just assumed it was a KLX kit.

I'll ride it for awhile and maybe swap back in the DJ kit just to compare.

One last question/verification: could my carb tuning be the cause of my overly hot Leo Vince? If so, how can I correct it? Is it too lean?

Matt

Typically.... HOT = LEAN, RESTRICTED or OVER WORKED!

Willie

 

[pdwestman]

I'll ride it for awhile and maybe swap back in the DJ kit just to compare.

Dave Pelletier could give you his suggestions on which clip groove, shim or no shim & Keihin Main Jet to use with your old kit needle, if it is indeed a DJ needle. (Did you use a magnifier?)

There is one more jetting kit Out-There, JD Jetting. Not to be confused with DynoJet (DJ). Can't remember if Dave has a pic of a JD needle or any experience with one.