klr650 : re-jetting

[Luc Legrain]

Could someone tell me what would be the benefits of re-jetting the carb on my 05? ____________________________________________________________________________________ Be a better Globetrotter. Get better travel answers from someone who knows. Yahoo! Answers - Check it out. http://answers.yahoo.com/dir/?link=list&sid=396545469

[Kyle]

--- In DSN_KLR650@yahoogroups.com, Luc Legrain wrote:

> > Could someone tell me what would be the benefits of > re-jetting the carb on my 05? > >

More raw power! Actually from the factory the bikes are tuned excessively lean for emission regulations. It`s really not necessary to rejet your carb unless you modify your exhuast which increases your exhaust flow. Which in return would make your bike run even leaner (hotter). This in a long term situation would damage your engine. So it would be necessary to rejet your carb to run richer (also cooler). Run to rich and this could also damage your engine with excessive carbon build up. Also your mpg would decrease. To rejet your bike just for the heck of it without any other mods would be a waste of time, you`ll only gain a couple of horesepower. I`m not going to blow my hard earned $$ on a new exhaust but I can`t stand tweeties lawnmower sound my bike puts out. Sometime over the winter I will do that exuast mod and kick tweety out once and for good. I hope it makes my bike sound alot better too. I`m sure I`ll have to rejet when I do this? I don`t claim to be an expert but this is my 2 cents worth.

[RM]

On Sat, 28 Jul 2007 13:11:37 -0700 (PDT), "Luc Legrain" said:

> Could someone tell me what would be the benefits of > re-jetting the carb on my 05?

Start with seating the pilot mixture screw, then backing it out 2.5 turns. You'll probably be so impressed with the off-idle throttle response that you decide not to bother with any rejetting. RM

[Doug Herr]

On Sat, 28 Jul 2007, Kyle wrote: [snip] > Sometime over the winter I will do that exuast mod and kick > tweety out once and for good. I hope it makes my bike sound > alot better too. I`m sure I`ll have to rejet when I do this? [snip] I assume you are talking about splitting the inner pipe. I don't remember anybody saying that this would lower the back pressure. Pretty sure you don't have to re-jet when killing tweety. -- Doug Herr doug@... A16 in Oakland, California

[Kyle]

--- In DSN_KLR650@yahoogroups.com, Doug Herr wrote:

> > On Sat, 28 Jul 2007, Kyle wrote: > > [snip] > > Sometime over the winter I will do that exuast mod and kick > > tweety out once and for good. I hope it makes my bike sound > > alot better too. I`m sure I`ll have to rejet when I do this? > [snip] > > > I assume you are talking about splitting the inner pipe. I don't > remember anybody saying that this would lower the back pressure. > Pretty sure you don't have to re-jet when killing tweety. > >

Actually I was thinking about doing this exhaust mod: http://www.klr650.net/forums/showthread.php? t=26151&highlight=exhaust+mod Remove the whole inner pipe and weld a 1.5" exhaust pipe over the whole where the pipe used to be.

[Doug Pippin]

Luc I agree with Kyle that the KLR comes jetted very lean from the factory but I disagree that there is no improvement in re-jetting with a stock pipe. I run a stock pipe to keep the bike quiet. This allows me to ride in stealth mode without disturbing the environment and people around me. However I have open up the air box and re-jetted the carburetor and the throttle response especially at the lower end and overall power is much better now. You don't have to buy an expensive jet kit as the parts you need to re-jet the carb are available at motorcycle shops at a much cheaper price. You will reduce the gas mileage if you re-jet. That doesn't bother me as I can still get over 200 miles to a tank of fuel. Be glad to share the final settings for the carb re-jet if you e-mail me direct. Doug in NC ---------- At 08:06 AM 7/29/2007, you wrote:

> Re: klr650:re-jetting > Posted by: "Kyle" kyle171@... cb750fs > Date: Sat Jul 28, 2007 2:16 pm ((PDT)) > >--- In DSN_KLR650@yahoogroups.com, Luc Legrain >wrote: > > > > Could someone tell me what would be the benefits of re-jetting > the carb on my 05? > > >---------- >More raw power! Actually from the factory the bikes are tuned >excessively lean for emission regulations. It`s really not necessary >to rejet your carb unless you modify your exhuast which increases >your exhaust flow. Which in return would make your bike run even >leaner (hotter). This in a long term situation would damage your >engine. So it would be necessary to rejet your carb to run richer >(also cooler). Run to rich and this could also damage your engine >with excessive carbon build up. Also your mpg would decrease. To >rejet your bike just for the heck of it without any other mods would >be a waste of time, you`ll only gain a couple of horesepower. I`m >not going to blow my hard earned $$ on a new exhaust but I can`t >stand tweeties lawnmower sound my bike puts out. Sometime over the >winter I will do that exuast mod and kick tweety out once and for >good. I hope it makes my bike sound alot better too. I`m sure I`ll >have to rejet when I do this? I don`t claim to be an expert but this >is my 2 cents worth.

---------- Doug Pippin 828-684-8488 d_pippin_89@... ---------- [Non-text portions of this message have been removed]

[Scott T.]

Definatly improvemnts to be had with rejetting to a stock pipe. I have an 08 and have gained huge throttle response and 7mph higher top speed. And i think there is more to be had once i remove the smog air pump vacuum line and jet up further. Cheers. Scotty --- In DSN_KLR650@yahoogroups.com, Doug Pippin wrote:

> > Luc > > I agree with Kyle that the KLR comes jetted very lean from the > factory but I disagree that there is no improvement in re-jetting > with a stock pipe. > I run a stock pipe to keep the bike quiet. This allows me to ride

in

> stealth mode without disturbing the environment and people around

me.

> However I have open up the air box and re-jetted the carburetor

and

> the throttle response especially at the lower end and overall

power

> is much better now. > You don't have to buy an expensive jet kit as the parts you need

to

> re-jet the carb are available at motorcycle shops at a much

cheaper price.

> You will reduce the gas mileage if you re-jet. That doesn't bother

me

> as I can still get over 200 miles to a tank of fuel. > > Be glad to share the final settings for the carb re-jet if you e-

mail

> me direct. > > Doug in NC > > ---------- > At 08:06 AM 7/29/2007, you wrote: > > Re: klr650:re-jetting > > Posted by: "Kyle" kyle171@... cb750fs > > Date: Sat Jul 28, 2007 2:16 pm ((PDT)) > > > >--- In DSN_KLR650@yahoogroups.com, Luc Legrain > >wrote: > > > > > > Could someone tell me what would be the benefits of re-

jetting

> > the carb on my 05? > > > > > >---------- > >More raw power! Actually from the factory the bikes are tuned > >excessively lean for emission regulations. It`s really not

necessary

> >to rejet your carb unless you modify your exhuast which increases > >your exhaust flow. Which in return would make your bike run even > >leaner (hotter). This in a long term situation would damage your > >engine. So it would be necessary to rejet your carb to run richer > >(also cooler). Run to rich and this could also damage your engine > >with excessive carbon build up. Also your mpg would decrease. To > >rejet your bike just for the heck of it without any other mods

would

> >be a waste of time, you`ll only gain a couple of horesepower. I`m > >not going to blow my hard earned $$ on a new exhaust but I can`t > >stand tweeties lawnmower sound my bike puts out. Sometime over

the

> >winter I will do that exuast mod and kick tweety out once and for > >good. I hope it makes my bike sound alot better too. I`m sure

I`ll

> >have to rejet when I do this? I don`t claim to be an expert but

this

> >is my 2 cents worth. > > > ---------- > Doug Pippin > 828-684-8488 > d_pippin_89@... > > ---------- > > > > [Non-text portions of this message have been removed] >

[E.L. Green]

--- In DSN_KLR650@yahoogroups.com, "Scott T." wrote:

> > Definatly improvemnts to be had with rejetting to a stock pipe. > I have an 08 and have gained huge throttle response and 7mph

higher

> top speed. And i think there is more to be had once i remove the > smog air pump vacuum line and jet up further.

FWIW, the '08 does not have a smog air pump. The thingy you see that looks sorta like a "pump" is actually a separator for handling condensate (fuel vapor from the gas tank that has condensed inside the evaporative emissions control system) and pumping it back into the gas tank. While removing it (and the rest of the evaporative emissions control system) has a number of benefits (the principle one being that when your bike falls on its side you no longer render it unstartable by filling a charcoal canister full of gasoline, just put a one-way valve in there to keep fuel from escaping when you fall over), better performance is not one of those benefits. -E

[Scott T.]

Actually yes the 08 49 state model does have a smog air pump.Kawi refers to this as the clean air system. It takes vacuum from a port on the forward righthand side of the carb wich operates a small pump located behind the coolant resivoir and pumps air into a steel tube wich is located over and conected to the exhaust ports through the top of the new cylinder head. Where the extra air helps to comlete combustion of unburned fuel in the exhaust. This has nothing to do with an evaporative emissions control system. And there is no charcoal can and it is not conected to the fuel tank. And as for the performance gains involved with remoing it? I,ll keep you updated when i have some bigger jets to try. Cheers Scotty

--- In DSN_KLR650@yahoogroups.com, "E.L. Green" wrote: > > --- In DSN_KLR650@yahoogroups.com, "Scott T." wrote: > > > > Definatly improvemnts to be had with rejetting to a stock pipe. > > I have an 08 and have gained huge throttle response and 7mph > higher > > top speed. And i think there is more to be had once i remove the > > smog air pump vacuum line and jet up further. > > FWIW, the '08 does not have a smog air pump. The thingy you see that > looks sorta like a "pump" is actually a separator for handling > condensate (fuel vapor from the gas tank that has condensed inside > the evaporative emissions control system) and pumping it back into > the gas tank. While removing it (and the rest of the evaporative > emissions control system) has a number of benefits (the principle > one being that when your bike falls on its side you no longer render > it unstartable by filling a charcoal canister full of gasoline, just > put a one-way valve in there to keep fuel from escaping when you > fall over), better performance is not one of those benefits. > > -E >

[grufrude]

--- In DSN_KLR650@yahoogroups.com, Luc Legrain wrote:

> > Could someone tell me what would be the benefits of > re-jetting the carb on my 05? >

Luc, I believe that the altitude where you live and use the bike the most has a bearing on the question you ask. I live at 6200' elevation and most of the riding I do around here ranges from 5500' to 9500'. My '06 KLR carburates perfectly with stock settings up here. Clearly that shows that the bike is jetted lean for sea level use, but for my riding area, stock jetting requires no changes.