natebal

xr650l mods: all or nothing?

52 posts in this topic

Hi, this is my first post here. Bought an 2002 xr650l two months ago. Though not my first bike, it has been several years since I have done much riding. Was stoked to find this site and it has been interesting to read about all the stock mods to increase performance on this bike. I must say when I first got it I was a bit surprised to hear of the lengths some of you were going to for more power on this bike, it felt pretty fast to me. Now that I'm used to it I could see how a little more zip could be good. Here's the thing, do you need to do all the usual stuff (bigger jets, desnorkel exhaust etc.), all at once? for example will the bike run crappy if you open up the air flow running stock jets or conversly leave the air intake stock and put in bigger jets? How would it be if you did the desnorkel and jets but left the stock exhaust? If doing the exhaust does a new tailpipe help without swapping the header pipes too? I Would like to maximise the potential of this bike but don't want to waste money and risk opening a can of worms, this bike runs perfect (if a little tame) as is(starts quick, idles perfect, acell pretty smooth, dosen't pop on decel), so I don't want to get greedy. Can it actually damage the motor to run this bike stock lean or is this just a power issue? Also it is possible that some of this(jets at least) was done by the original owner. The bike came with a clarke tank, renthal bars, aftermarket knobs, answer 48th sprocket and uni filter, and looks as if an oil cooler was once mounted, so it wouldn't surprise me. I got the bike from a small shop that was clueless and the original owner is unavailable for comment. Is there a way to check the jetting for part 3 or something without taking the carb apart? aAny help much appreciated. Also im at sealevel Nate

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Hello and Welcome to TT

If it was me and the bike runs as good as you explained in your post. I would just ride that baby. I've got about 16,000 miles on mine now and I have done some mods. to it. These bikes are bullet proof. It has not given the first bit of trouble. I did remove the jet kit from my carb. because of gas mileage and it didn't make that much difference in power. I went from about 55 MPH to 40 MPG and with the gas prices like they are I pulled that jet kit out. I did go up one size on the main jet from a 155 to a 160 to see how it would do. It does a great job. Again welcome to TT hope this helps. :ride::ride:

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I have to agree. I owned a 650L a few yrs back & spent a ton of money on aftermarket stuff to make it faster. In hindsight none of it made that significant of a difference. Though I hate to admint it, the single best mod I made to the bike was a set of electric handwarmers. I can't believe these are not more popular! Anyway, ride it awhile. You will then have a better idea of what might make the bike better for you personally. Enjoy it & be safe! God bless.

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Thanks for responding, I guess I'll leave it as is for a while, would hate to ruin a good thing. Purrs like a kitten, why mess with it I guess.

Nate

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There's nothing saying that these XRL mods are absolutely necessary. For the most part, they aren't that expensive. One thing that people get confused about is the "power" issue. You're not gaining any more power. All you're doing is improving the performance & driveability of the factory choked-off motor. Although, after doing the carb, exhaust & air box mods, it may "seem" like you've gained more "power."

If you want more power, then it's time to tear into the motor. But unless you've got an unlimited budget or your motor's already blown, then I wouldn't worry about it. These motors are built to last & they're bullet-proof, mods or no mods.

As for an opinion regarding stock vs. uncorked? Uncorked is far better than stock. :ride: But that's just me & for how & where I ride my machine...

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The only thing Ive done to my L so far is to remove the emissions nonsense.

I have jetted and piped most all my bikes and quads over the years, and not once did i notice less power :ride:

Granted you are not gonna gain lots of horsepower , but you will gain

a better responsive throttle and snappier power band.

On my quad after jetting and piping i could throttle up a wheelie in 3rd gear as opposed to

a second gear throttle up wheelie before modding.

I would not hesitate to let your bike run at its most potential , for the few bucks it would cost.

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Easiest way to gain more power in any engine is increasing the amount of air and fuel intake, and exhaust output.

Thats why a 671 blower of turbo works so well, more air and fuel shoved rapidly through the cylinder, but the valves and exhaust have to be able to relieve the mugh higher amount just as fast.

If you drill your slide, install the right jets, add a Uni filter and remove snorkel, and install a good pipe that lets all that new burnt gas out quicker, you wont believe the huge power gains.

I would rather have the needed power for offroading and the ocassional street blast, than worry about a little loss in mpg (very minimal vs huge power gains)...since I dont commute or rack up street miles on my L.

When I bought my bike it was showroom new looking with only 600mi. It was perfect, or so I thought until i found this site and a few others and heard about a Dude named DAVE !!!

Now it is the funnest bike I have owned (sportbikes,dirtbikes,harley,trials,etc.) and most versatile machine around.

Did someone say "Best bike in the world" ???

word up

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Pipe, Cam, Carb, Piston, Gears, Filter, Big tank and friggin crank the thing because it will work 10 times as good as it used to.

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Easiest way to gain more power in any engine is increasing the amount of air and fuel intake, and exhaust output.

Thats why a 671 blower of turbo works so well, more air and fuel shoved rapidly through the cylinder, but the valves and exhaust have to be able to relieve the mugh higher amount just as fast.

If you drill your slide, install the right jets, add a Uni filter and remove snorkel, and install a good pipe that lets all that new burnt gas out quicker, you wont believe the huge power gains.

I would rather have the needed power for offroading and the ocassional street blast, than worry about a little loss in mpg (very minimal vs huge power gains)...since I dont commute or rack up street miles on my L.

When I bought my bike it was showroom new looking with only 600mi. It was perfect, or so I thought until i found this site and a few others and heard about a Dude named DAVE !!!

Now it is the funnest bike I have owned (sportbikes,dirtbikes,harley,trials,etc.) and most versatile machine around.

Did someone say "Best bike in the world" ???

word up

" Best bike in the world ! " ... I just HAD to say it ! ... :ride:

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Man I hate when someone states the obvious...

you either get it or you dont right?

ha ha ha !!!

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If the bike came with a UNI filter, it probably was re-jetted. Check your plug for color. If it's white re-jet, if it's tannish you're good to go. The most performance you'll gain is by shaving pounds from the bike. :ride:

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Well it all depends on how much you are willing to spend...

I see it as sort of 2 different stages. First is uncorking. Every Honda XR is corked to some degree. Uncorking that makes it run the way it's supposed to. Second is real engine mods. Stuff like higher compression and performance cams. As a rule mods are much more expensive.

To uncork you need to:

  • Remove airbox snorkle
  • Replace stock air filter
  • Carb - rejet and if desired drill slide
  • Open up exhaust.

Drilling the slide gives a little better throttle response.

I didn't ditch the stock pipe on my XR600. I am running an aftermarket insert. It really made a huge difference. If you go with an insert, it should only cost a little over $100 to make all the changes.

If you remove the smog stuff, keep it just in case California starts smog checking road bikes. Keep the snorkle and exhaust for the same reason

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Thanks for the replys, ghoti, I too suspected that this bike was already rejetted as the throttle response was smooth and the bike pulls strong and doesn't pop on decell, as the modded bikes are described in the forums. Thats why at first I couldn't relate to the reports of this bike bogging and being slow. This is my first XR but it feels pretty good. I'll check the plug for a clue, thanks. Also are there marks on the jets themselves that say what size they are or just on the packageing they come in. However,I tried the "roll-off" technique and did notice a mild power increase when throttling back to 7/8 from full in fourth gear wound up. Will thiis happen with ideal propper jetting a little still, 'cause it was subtle, yet there for sure. the airbox looks to be unmodded though, which makes me wonder. This may be a dumb question but what exactly is the "snorkel" and how do you take it out. Also, to uncork the stock pipe the end looks like it is welded on . Is this stock, or do you cut off the end , remove the baffle and weld it back on. The weld looks a little homegrown as if somone did this already but the bike is pretty quiet , too quiet it seems for all the baffling to be gone. should I just get another pipe? not too psyched too thow useless money at it but now I'm really gettin curious. Still feeling greedy as this bike really purrs, but never enough right?

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The "snorkle" is a rubber or plastic insert that goes in the hole that lets air into the airbox. Just yank it out of there. When it's gone the hole is larger and allows more air in. This is usually the first "mod", so it's most likely already long gone.

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1995 XR650L purchased new in May 1996.

I am one more here for leaving it stock.

I only desmogged mine, foam filter and removed the snorkel. Not rejetted. At 5000 feet asl, it's been okay with the lean jetting. Non DOT tires are always a MUST.

After nearly 60,000 hard miles, and still pounding, it is without a doubt my favorite motorcycle, ever. For me, it IS the best motorcycle.

Versatility, Dependability, and Lethality!

I just had to throw that last one in there...

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1995 XR650L purchased new in May 1996.

I am one more here for leaving it stock.

I only desmogged mine, foam filter and removed the snorkel. Not rejetted. At 5000 feet asl, it's been okay with the lean jetting. Non DOT tires are always a MUST.

After nearly 60,000 hard miles, and still pounding, it is without a doubt my favorite motorcycle, ever. For me, it IS the best motorcycle.

Versatility, Dependability, and Lethality!

I just had to throw that last one in there...

Dude 60,000 miles really? holy shit! thats awesome, now I know what to look forward too :ride:

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1995 XR650L purchased new in May 1996.

I am one more here for leaving it stock.

I only desmogged mine, foam filter and removed the snorkel. Not rejetted. At 5000 feet asl, it's been okay with the lean jetting. Non DOT tires are always a MUST.

After nearly 60,000 hard miles, and still pounding, it is without a doubt my favorite motorcycle, ever. For me, it IS the best motorcycle.

Versatility, Dependability, and Lethality!

I just had to throw that last one in there...

60,000 miles for a XRL honda thats just getting it broken in. LOL. These bikes are bullet proof. I'll tell you what made me a true Honda guy. I had a 1976 XL250 that I cracked the side case on. Rather than fixing it I would just add oil from time to time. I was out riding one day and I noticed that it was losing power and getting slower. It finally locked up because I had forgot to put oil in it. I let it cool down and tried to ride it home. It locked down again. I hauled it home and pulled the spark plug out and filled the cylinder with oil. The next day I broke it loose withe the kick start. I put the spark plug back in and it fired right up. I rode that bike for about a year after that and sold it. Its was still running good when I sold it. Thats why I like Honda so well. :ride::ride::ride:

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I just did the mods to a 1994 XR-L I picked up with only 2700 miles on it.

De-smog

De-snorkel

UNI Air Filter

Drill/shim/jet carb

FMF Q muffler

I'm very, very happy with the results of the changes. They work spot on and I can tell a seat of the pants difference in power and improvement in throttle response. I went with a 160 on the main since I put on the aftermarket exhaust. Dave's mods are for the stock exhaust. The snorkel, air filter, and jetting should be done together in my opinion. The FMF pipe is barely louder than stock but sounds quite a bit better.

The snorkel on my L was riveted in so I did have to drill those out, might be different on other years.

If your bike accelerates slightly when you barely let off WOT, then it usually means your main is a bit big, which would tell me your bike may have already been jetted. Check your plug. The plug on my stock L was very light tan, almost white.

Jets are made of brass if you've never seen one and have their size stamped onto them someplace. Sometimes hard to read, but it's there.

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Hey guys, I am new to the sight also... Lots of good info in here..

Just got me a 95 xr650L, it has 2000 miles on it now... Its all stock except for the k & n air filter that i just installed.. It is much easier to start now with the k & n.. (no choke)

Does anyone else run a k & n filter??

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I have an XR650L in Botswana and did everything suggested above except desnorkeling.  Did that today and what a difference!  Very hard to get parts out here... next thing I want to do is the front fork stabilizer.

Keep the wind in your face

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