[jameslogan23]

Opinions-Most Important Performance Mods

I just sold my '05 636 Ninja. Now the only street legal bike I currently have is my good 'ol '06 KLR 650. I've loved the bike for what it is and have put over 10k miles on it over the last 2 years (a fair amount owning 3 bikes). But now that I no longer have my Ninja, I would like to try and add a couple horses to my KLR and NEED YOUR HELP!!!
Listed in order of priority, I want to:
1) Add power
2) Not effect the classic bulletproof durability
3) Increase or keep the MPG the same

What should be my top 3 priorities to accomplish the above if I plan on spending
1) $500
2) $750
3) $1000

Please list specific recommendations (i.e. Big Gun vs FMF, slip-on vs full, ect).

I'm looking forward to what everybody has to say and THANK YOU in advance!
P.S. I'm purchasing my first aftermarket item today- 6.6 gallon IMS tank!

 

[Spec]

I just sold my '05 636 Ninja. Now the only street legal bike I currently have is my good 'ol '06 KLR 650. I've loved the bike for what it is and have put over 10k miles on it over the last 2 years (a fair amount owning 3 bikes). But now that I no longer have my Ninja, I would like to try and add a couple horses to my KLR and NEED YOUR HELP!!!
Listed in order of priority, I want to:
1) Add power
2) Not effect the classic bulletproof durability
3) Increase or keep the MPG the same

What should be my top 3 priorities to accomplish the above if I plan on spending
1) $500
2) $750
3) $1000

Please list specific recommendations (i.e. Big Gun vs FMF, slip-on vs full, ect).

I'm looking forward to what everybody has to say and THANK YOU in advance!
P.S. I'm purchasing my first aftermarket item today- 6.6 gallon IMS tank!

1st welcome to the forum.

OK here's the deal with a KLR. It's a 35 horsepower motor that won't generate much more horsepower without significant work. An aftermarket pipe won't help it out much but it will make it louder so save your money. Spend about $400 for a 685 kit and you'll gain about 3 horsepower. Spend about $1000 and get the 685 kit, get the head worked on, oversize valves and a pipe and you get about 10 horsepower. There's also a 700 cylinder kit that's about $500 more. Gas mileage and reliability have an inverse relationship to engine mods normally!

Patman has a good dyno page on KLR mods here.

Even if you do get 10 more horsepower it's still a slow reving old tech motor. Going faster leads to wanting the brakes to work better leading to wanting the suspension to work better. See where this is going?

 

[jameslogan23]

I saw online a motorcycle shop that added only a Jardine slip on exhaust and they dyno-ed it at 34 hp before and 37 hp post. Also a gain of 3 hp. Does that sound right? If I did get an exhaust, is it worth the whole exhaust or just the slip on?

I probably won't bore it out until I have quite a few more miles. Even though I plan on buying a 3rd bike, I don't ever plan on selling this one. I'm a follower of "when it breaks, upgrade" , so eventually it will probably be pretty well mod'ed out.

 

[Damocles]

I saw online a motorcycle shop that added only a Jardine slip on exhaust and they dyno-ed it at 34 hp before and 37 hp post. Also a gain of 3 hp. Does that sound right?

Short answer, "No."

Someone on ADVRider.com offers a prize (think it's $ 50) to anyone who dynos a modest rear-wheel horsepower increase, with mere carburetion and exhaust tuning; NO ONE HAS EVER COLLECTED.

A problem with trick exhaust horsepower curves, compared to STOCK exhausts, sometimes the aftermarket curves are LOWER, at certain strata . . .

And, what is your service life spectrum for your KLR? At maximum horsepower almost constantly, or a little beyond, approaching redline? Are you in COMPETITON riding? Answers to these questions may help you justify your hop-up, or . . . bring you to . . . I would say, "to your senses," but that's too judgmental; let me say to perhaps more conservative and realistic goals and objectives.

As Spec says, hop-up leads to a CHAIN of inter-related systems; and . . . you know about the weakest link. If you're going to coax more oomph out of the tractor engine, you're going to stress components not designed for the added loads; FORGET ABOUT static durability and reliability, as you attack the World Land Speed Record, or your hometown main street grand prix lowest-recorded-lap-time mark.

The modest modifications suggested, increasing displacement by 5 % (i.e., 685 kit), may bring about 5 % more peak horsepower and torque, without seriously compromising reliability (although, men say, for every stress there's a strain; "no free lunch").

Worth it to you? Only you can decide.

-----------------

Then again, some forum members claim you will obtain additional horsepower, greater fuel economy, decreased oil consumption, enhanced engine compression braking, and improved ring seating by merely installing a check-valve in the crankcase breather hose (the "PCV Valve Mod").

Imagine, all these advantages for just the price of a PCV valve and a couple of hose clamps; MUCH more economical than an aftermarket muffler! Quieter, too!

FULL DISCLOSURE: I personally remain skeptical of the claimed advantages of the PCV valve mod, because . . . I know of no tangible, repeatable, measurements of any of them, beyond the accuracy, precision, and repeatability of the error budget of the measuring devices used (e.g., dynamometer), nor . . . has the MECHANISM whereby a check-valve works all this magic been explained to my understanding (no crankcase vacuum has ever been detected, although I've no idea how a vacuum could work these wonders, even if it existed).

 

[ShadetreeAZ]

Umm, how bout just back off a bit and deal with what you got. Save the dough until you figure on something that works for what your ride is and needs to be. Yea I know, easy for me to say. Good luck.

 

[Lockjaw]

Quickest, cheapest way. Lose 15 pounds. Seriously.

 

[planalp]

Welcome to the forum. You've had the KLR for 2 years and have logged over 10,000 miles on it. In what situations did you wish you had more horsepower? Highway riding or off-road? If the former, can't really think of anything you can do to significantly improve things besides spending a lot of money with no noticeable gain in performance. The latter? Perhaps a sprocket change?

Just something to think about.

 

[C29g]

I feel the klr's throttle is sloppy. it has its points where response is there then falls on its face through the rev range. I too am curious to find a tune that gives a more crisp throttle response through the rev range. been looking at re jetting, but i cant find a tune that seems justifiable. and concrete. I spend alot of time off road at old mines, and on the highway. the suspension sucks, and the bottom end power seems to be sufficient, but as you climb and and rip into the throttle it seems to die a bit at around 36-5500 rpm, i would assume an upgrade to my main jet would solve this but Im new to tuning any thoughts?

 

[pdwestman]

C29g,
Sorry, but not enough info about your bike, its condition or previous mods and your location to suggest anything other than 100% stock and standard jetting as a starting point with a perfectly clean carburetor.

 

[Damocles]

I too am curious to find a tune that gives a more crisp throttle response through the rev range. been looking at re jetting, . . .

Expectations from "jetting" remain . . . EXAGGERATED!!!!!!!!!!!!

Stock jetting offers an air/fuel mixture across a wide operational spectrum close to optimum.

Mid-range operation can be fuel-enriched by shimming the needle, idle mixture fuel-enriched by opening the fuel screw some . . . but the stock main jet and stock needle, by all accounts, result in a wide-open throttle mixture PLENTY fuel-rich.

You can hog-out the vacuum port in your slide to 7/64" diameter; then, convince yourself you've improved throttle response.

Otherwise, don't expect World Land Speed Records from "jetting" your carburetor. That said: Feel free to dyno your stock bike, buy a jet kit, then dyno the final result, proving me wrong!

 

[Bluehighways]

A KLR is NOT a bike that will do much to reward a tuner. Best solution if more power is needed would be to sell the KLR and then buy something else.

Folks that want to soup up a KLR remind me of the old cartoon of the Snail on a Turtle's back yelling "We-e-e-e-e-e-e-e!"

 

[C29g]

I'm not looking for supersport performance from my KLR , with replacing the exhaust (to get rid of the mind numbing chirp) with a LEXX, my bike is stock. BIke has 28k miles on it, top end has been rebuilt valves shimmed, valves relapped, valve springs replaced, and aside from that... standard oil change intervals, and filter replacements. All i was referring too on the throttle was when i'm off road hill climbing, for example, when i hit second on my run up its power is not smooth past 3500, which as far as i have read the needle supplies for 3500< the jet takes over 3500> however I'm not a carb expert. that's why i believe the original poster and I am looking for ideas to improve this. Not a bunch of peoples opinions on what they think we expect from a 30hp single cyl #400 bike. My Drz 400 is not as sloppy in the rev range as the old tractor is that is what perked my curiosity.

 

[pdwestman]

Have you been into the carb? Is it 100% stock and standard? Did you write down the jet numbers? Is the pilot mixture screw un-capped? How many turns open is the pilot mixture screw? Is it 100% clean? What altitude are you at? Do you ride UP from there? Or Down from there? Or both?

Has the air box snorkel been removed? Has there been 4 one inch holes drilled into the cross frame section of the air box? Has the access door been thrown away?

 

[C29g]

i have cleaned the carb every 5k miles, its never had the cap is still there, i ride between 450'-600' alt. 148 main jet. and no i haven't taken out the snorkel or modded the air box as when i say i ride quite a bit off road, I live around alot of clay and its usually pretty wet here i have hit water holes nearly 3' deep and pinned the throttle just to push water away as much as possible to attempt to keep from drowning it in water. I have drowned it a couple of times lol. not trying to build a drag bike just looking to fine tune it a bit.

 

[DPelletier]

i have cleaned the carb every 5k miles, its never had the cap is still there, i ride between 450'-600' alt. 148 main jet. and no i haven't taken out the snorkel or modded the air box as when i say i ride quite a bit off road, I live around alot of clay and its usually pretty wet here i have hit water holes nearly 3' deep and pinned the throttle just to push water away as much as possible to attempt to keep from drowning it in water. I have drowned it a couple of times lol. not trying to build a drag bike just looking to fine tune it a bit.

removing the snorkle does nothing detrimental as far as deep water crossings go: the air entrance is at the same height as always. The "standard recommended setup" is as follows;

- KLX jet kit and snorkle-ectomy. Follow the instructions in EM's kit. optional items; Uni filter, L mod or 4 - 1" holes in the airbox lid (lid is higher than the snorkle intake) and the silencer of your choice.

Unless you want to start looking at BB kits, porting, etc. that's the cheap and easy way to get your KLR running as it should......hp won't be up much but the poor factory jetting condition will be corrected and throttle response improved.

Dave

 

[pdwestman]

I believe that by "air box lid", Dave actually means the cross frame air duct between the frame rail and the rear fender. Not the air box door on the RH side.

 

[DPelletier]

I believe that by "air box lid", Dave actually means the cross frame air duct between the frame rail and the rear fender. Not the air box door on the RH side.

Yes, that's exactly what I mean, thanks for clarifying. I don't recommend running without the airbox door for several reasons, most of which should be obvious. When modifying the top of the airbox, ensure you stay on the dirty side! ;-)


Cheers,
Dave

 

[C4HOON]

Old thread yes but
Start by chucking the standard carby away and put in a big makuni pumper carb , get rid of the crap restricting air box and put in a big kn filter and hose to match the carby. They use these on motocross so can wet and muddy without any into the carby etc A new aftermarket exhaust and replace the doo hickey with a eagle mike one and tune it all to match . If ur highway use put on some good road tyres and a 16 tooth sprocket and the response is amazing when u twist that throttle it has balls now and pulls hard and will overtake with ease . Loose both sides fairings that are between the tank and dash fairing and trim the windscreen down and it will surprise you what loosing alittle weight on the klr will do .
it will cost a few grand for all that with new piston and rings and head rehone and new valves etc but u won't regret it. I've done all this on a 2009 klr650 and it now rocks and I daily mine