after 9 years stock, my evaluation of Dave's Mods

[Itchykawa]

I have owned 2 stock 650Ls for a total of 9 years and just completed Dave's Mods and the rest of the uncorking process for the 1st time. Dave's Mods, smog block off kit, K&N filter, and tossed the snorkle. Here are my observations:

After YEARS of fighting the cold-natured beast and never knowing for sure if it was going to start in the morning or if I would have to push it off, she now fires right up in an instant and is ready to ride in a minute or two - even on cold mornings. HALLELUJAH!!! This alone is reason enough to do the mods in my opinion. Shame on Honda for giving us our Pigs in such a sorry state. How will we ever start our bikes in say... 2025 if the smog nazis have their way?

If you are expecting MAJOR changes in performance you will be disappointed, but the gain IS noticeable. Throttle response is much improved and the bike feels and sounds as if it isn't working nearly as hard to do the same things. On backroads it is now possible to just leave it in 5th gear and ride at almost any speed no matter what comes your way. Need to slow for a curve or climb a long incline? Don't down-shift, just roll on a little more throttle and feel the engine "chug" right along. Need to blow around that chicken truck? Just whack the throttle in almost any gear at any speed and she will happily comply. In the dirt there is more "grunt" for the really tough stuff and the engine seems cooler too.

I have read that 90% of the engine "popping" goes away with the smog pump.... ALL OF THE POPPING and other funny little noises on deceleration are gone from my bike - TOTALLY as far as I can tell. Another single reason good enough to warrant doing the Mods.

I have never kept up with fuel economy and miles per gallon, but I have put almost 700 miles on her (in only 2 days ) since the mods and have noticed no major loss in fuel mileage. I would gladly give up a few MPG though if that is what it costs me. I believe the gains will mostly offset any losses because it now takes less throttle to do the same job. Those who complain about a loss of MPG probably can't control their right wrist. A friend, who did his mods together with me, says his XRL got well over 50 MPG on a 300 mile ride we took last Sunday.

There is no excuse important enough not to do these simple, inexpensive mods.? Thanks Dave!

Cheers!

[Wild Turkey]

That's exactly what I wanted to hear! I'm getting ready to do these mods to mine, I'm just waiting on some more parts. Glad it worked out good for you. ?

[durandal]

Thanks for the great report.

As soon as I get around to looking inside my carb (to see if the P.O. changed the jets or not) I'll order those jets. The popping is irritating, and there's a flat spot somewhere on the power-vs-throttle curve that is driving me nuts. It's tiny, but I can feel it.

d.

[paul246]

Good to hear, I hope to do the mods this year on my L, if I ever get the time that is.

[lilbro]

9 years? I didn't last 9 days before uncorking.

[martinfan30]

Amazing what happens when they get fed the fuel they need! The MPG loss is prob from you on the gas all the time! I run a hotcam, FCR 41, and modded exhaust... If i'm easy on it, I can still get up to 45 MPG.

[Denn10]

those 2 bikes for 9 years did you have stock jetting in it? I like you noticed just a little bit but definitely worth it i think.

[sploogemonkey]

I had my bike for five years before I did anything to it. It's a '00 600R that I bought used in 12/02.

In five years of owning it, I think I only rode it about 12 times, probably less than 250 miles total.

About November '07 I finally decided to mod it and start riding it. It was completely bone stock, hadn't even had the restrictor taken out of the air box.

The fact is that now that I've modded it, I like it even more. ?

I noticed a definite power increase across the board. I've ridden it more in the last three months than I have in the last three years combined.

[paul246]

Can the required jets be bought seperately or would I have to order a "kit"?

[martinfan30]

Can the required jets be bought seperately or would I have to order a "kit"?

Yes you can go to any motorcycle shop and order a 158,160 or 165 main. Same with the pilot jet. Make sure you shim and drill the slide as well.

[Denn10]

there around $4/5 for the jets and if anyone need a washer i have a few more.

[dldavis_66]

When Honda sets these bikes up at the factory in Japan they are jetted and tuned for elevations of at least 2000 feet above sea level and up to 3000 feet above sea level. That in itself in appreciable.

What I fail to acknowlege is why Honda decided to pick on the XRs to power them down so much and make them so smog compliant. I mean, why such a low compression piston? 8.3:1? Get real. Might as well have a 2 stroke with that low of compression. Can't be for smog. Many of the Honda sport street bikes with bigger engines than the XRs come with at least 12:1 compression right out of the box. Were to many people getting hurt with higher compressions on the XRs on the street and dirt? Who came up with the hair-brained idea of putting a smog pump on a motorcycle anyways??

Almost everthing about the stock configs for the XRs restricted power train is stupid and totally senseless:excuseme: . I guess Honda is entitled to some brainfarts every now and then.?

[martinfan30]

When Honda sets these bikes up at the factory in Japan they are jetted and tuned for elevations of at least 2000 feet above sea level and up to 3000 feet above sea level. That in itself in appreciable.

What I fail to acknowlege is why Honda decided to pick on the XRs to power them down so much and make them so smog compliant. I mean, why such a low compression piston? 8.3:1? Get real. Might as well have a 2 stroke with that low of compression. Can't be for smog. Many of the Honda sport street bikes with bigger engines than the XRs come with at least 12:1 compression right out of the box. Were to many people getting hurt with higher compressions on the XRs on the street and dirt? Who came up with the hair-brained idea of putting a smog pump on a motorcycle anyways??

Almost everthing about the stock configs for the XRs restricted power train is stupid and totally senseless:excuseme: . I guess Honda is entitled to some brainfarts every now and then.?

Its got to be something to do with CARB or the EPA as far as street legal dirtbikes. Im not familiar with smog laws... We dont have ANY!

[paul246]

When Honda sets these bikes up at the factory in Japan they are jetted and tuned for elevations of at least 2000 feet above sea level and up to 3000 feet above sea level. That in itself in appreciable.

What I fail to acknowlege is why Honda decided to pick on the XRs to power them down so much and make them so smog compliant. I mean, why such a low compression piston? 8.3:1? Get real. Might as well have a 2 stroke with that low of compression. Can't be for smog. Many of the Honda sport street bikes with bigger engines than the XRs come with at least 12:1 compression right out of the box. Were to many people getting hurt with higher compressions on the XRs on the street and dirt? Who came up with the hair-brained idea of putting a smog pump on a motorcycle anyways??

Almost everthing about the stock configs for the XRs restricted power train is stupid and totally senseless:excuseme: . I guess Honda is entitled to some brainfarts every now and then.?

Given the fact that I operate my bike very close to 2000' ASL, should I just leave the factory jets in place but still do the drill and shim mods?, along with Uni filter, desmog??

[martinfan30]

No... Those stock jets are even too lean at my altitude, 4300 ft. I run 158/55 here. Alot of guys down in CA. near sea level run 160, 165 mains. I think its well worth it for you to jet richer. Cooler engine temp, better power, less decel popping....

[Itchykawa]

Given the fact that I operate my bike very close to 2000' ASL, should I just leave the factory jets in place but still do the drill and shim mods?, along with Uni filter, desmog??

No - definitely change the jets also. 55/158 should work fine. ?

[Itchykawa]

those 2 bikes for 9 years did you have stock jetting in it? I like you noticed just a little bit but definitely worth it i think.

I bought a new '94 model and rode it till '02. It was basically stock when I sold it except for a Super Trapp exhaust. I bought an '06 last year and it is the bike I just modded.

The small gain in performance is certainly worth the effort, but the easy starts and better sound is icing on the cake!

[Purcell69]

Well my Uni Filter arrived yesterday so as soon as the weather here cooperates, I'm pulling the snorkle and installing the Dyno Jet kit. I pulled the smog equipment about a week ago and I really like being able to see the side of the motor instead of a bunch of hoses. I know the Dyno jet ket produces similar results as Dave's Mods.

Not to hijack this thread, but...

I also read in another thread that I can't find, that the 160 jet is to be used with the desnorkled air box and Uni Filter, but the paperwork with the kit says it is for the stock airbox and filter. Should I go with the 165 jet? I'm at 900' and still have the stock pipe, for now, on my '07 XRL.

-Joe

[Itchykawa]

Well my Uni Filter arrived yesterday so as soon as the weather here cooperates, I'm pulling the snorkle and installing the Dyno Jet kit. I pulled the smog equipment about a week ago and I really like being able to see the side of the motor instead of a bunch of hoses. I know the Dyno jet ket produces similar results as Dave's Mods.

Not to hijack this thread, but...

I also read in another thread that I can't find, that the 160 jet is to be used with the desnorkled air box and Uni Filter, but the paperwork with the kit says it is for the stock airbox and filter. Should I go with the 165 jet? I'm at 900' and still have the stock pipe, for now, on my '07 XRL.

-Joe

Joe,

Dynojet numbers are different from Keihin's. I operate from 800' ASL to 2500' ASL with K&N filter, no snorkle, desmogged, and slight mods to the stock exhaust for better flow and sound. 55/158 Keihin jets with air screw at 2 1/2 turns out and slide drilled to 5/32 seems to work perfect for me. I am keeping the 58/160 jets in case I ever want to go with "full race" exhaust or operate at extremely high elevations.

[dldavis_66]

I am keeping the 58/160 jets in case I ever want to go with "full race" exhaust or operate at extremely high elevations.

If you want to go with a "full race exhaust" a 160 main will be too lean IMO. I've got my homemade headers which have a higher rate of flow than stock and probably most aftermarket headers. After installing my homemade headers, the engine ran kinda lean and I did lose some bottom end, even with a DynoJet 165 main. I didn't want to go to the next higher up main which more than likely would have had to be a 170. So, instead, I raised up the needle 1 notch and that did the trick. The engine has run beeeeautifully ever since.

If you go into extremely high altitudes, a 160 main will not help you at all. Remember, the higher you go, the leaner the mix, therefore, smaller jets would be needed.