Mild to wild - uncorked XR650R

[Chopp]

So I have an '06 XR650R with about 200 corked up kilometers on it. I decided to uncork this thing and did the usual drill:

airbox snorkel/plastic thing out

175 main

68s

needle in the third or middle position

UNI air filter

Comp spark arrestor

drilled intake manifold

I am by no means skilled at mechanical stuff, but this was pretty easy. This thing sounds like a beast now. Can't ride it yet cause the temperature dropped to about -10 Celsius so its too damn cold. So it is killing me to see the performance difference.

I have two questions - With all the above mods I did, how would it run if I left the stock spark arrestor in the muffler instead of using the comp spark arrestor? Only reason I ask is that it is a tad noisy for 0430 hrs drives to work.....

Secondly, I couldn't get that stock metal screen to fit behind my UNI air filter.... will that be a problem?

Thanks for the help... if it wasn't for this site I wouldn't have been able to uncork this beast myself.

[BCBrouwer]

The stock backfire screen comes out when installing the uni filter, it has a plastic cage built in to hold it in place. plus, this aids in more airflow.

I find with the spark arrestor, the bike is like a monsterous powerfull animal that has to breath out of a straw (stock arrestor) and roars to life when it can breath out unrestricted. on mine with similar mods, the stock baffel makes the power much more mellow both in power and sound. it also messes with the jetting, you can put the stock one in, but may have to lean out the jetting a little. try and see, one step at a time. I know there are aftermarket baffels that are quieter than the stock honda racing one and still have no comprimise on power. maybe others can help you out which ones to look out for

[motopsycho650]

If you want more, cut out the side panel covering the air filter. You'll probably have to up the main jet to a 70s, and possibly the main one size. But, I promise even more of a gain over the initial uncorking.

[gringo1450]

So it is killing me to see the performance difference.

Be careful it might

I uncorked and it felt like 50% more power

It spit me off going through the woops and now I am sitting here with broken ribs.

but I did get back on to try my new Motard wheels

I think I will ride the street until I get a better feel for the PIG

[Chopp]

While standing in my garage admiring my handy work and revving the engine I noticed there seems to be considerably more throttle response. Starts sooo much easier, and it is still cold here.

It sounds very different when I kick it over as well which almost makes me think I put something back together wrong.... so that has me concerned a bit.

I am going to run it as it is for now and I might cut the side out of the airbox cover later if not satisfied.

Riding it when corked up was a little on the dull side and I was thinking I should have got another DRZ400 with E start. I have a funny feeling that there is now going to be a huge difference.

[XRR-kat]

You'll get another 1,000 rpm by drilling the air box side cover...might even hit rev limiter (8200 rpm).

[InternalCombustion]

A fully uncorked 650R has to be experienced to be believed. Even then you still grin like an idiot.

Like xrr-kat and motopsycho suggest, side vents add a nice extra hit and if you take your time on the mod-job, it looks soooo sweet. (See My Garage for pics of my Johnny Campbell copy-cat)

Trust me, no full-throttle 1st or 2nd gear until you are sure you're ready.

So freaking much fun.

Ride safe.

[Chopp]

OK, so it was -5 degrees celsius today but sunny and no wind. I took the bike out for a rip on the street. The bike seems to pull nicely thru all the gears, only hit about 80 MPH because it was too cold with the wind. It sure got to 80 MPH in a hurry.

The front wheel will come up with just throttle in 3rd gear - which it couldn't do before. Didn't try 4th though. There seems to be a bit of popping in deceleration, so I will have to adjust something to sort that out.

Bike is louder but managable if I don't goose it until I leave my neighborhood. Everybody here has loud trucks, snow machines, bikes....so I should be ok as far as complaints go.

Overall I am pretty happy.

[InternalCombustion]

Mild popping on decel is generally considered normal for most correctly tuned 650R's. Mine does, maybe one pop every second or so, depending on gear and speed.

[slotcarrod]

OK, so it was -5 degrees celsius today but sunny and no wind. I took the bike out for a rip on the street. The bike seems to pull nicely thru all the gears, only hit about 80 MPH because it was too cold with the wind. It sure got to 80 MPH in a hurry.

The front wheel will come up with just throttle in 3rd gear - which it couldn't do before. Didn't try 4th though. There seems to be a bit of popping in deceleration, so I will have to adjust something to sort that out.

Bike is louder but managable if I don't goose it until I leave my neighborhood. Everybody here has loud trucks, snow machines, bikes....so I should be ok as far as complaints go.

Overall I am pretty happy.

Where are you in Alberta?

You did not say if you cut out or replaced the rubber intake manifold in front of the carb. This is a must! If you are not good with a Exato knife and Dremel sp?, here is the number for the Carb Insulator # 16211-MBN-640.

I am in Calgary and have a uncorked BRP. The altitude is just over 3000 ft in Calgary.

I use a 170 main. You must buy part # 16012-MBN-641 B53E needle (in the 3rd clip position for most of Alberta). The 68S should be perfect for most of Alberta as well.

Use these charts to help you jet for your altitude! http://www.xr650r.us/jetting/

This site http://xr650r.us/ is great and will help you with your BRP.

[slotcarrod]

ps: My bike with propper jetting, no popping. Sweet!

[Chopp]

Where are you in Alberta?

You did not say if you cut out or replaced the rubber intake manifold in front of the carb. This is a must! If you are not good with a Exato knife and Dremel sp?, here is the number for the Carb Insulator # 16211-MBN-640.

I am in Calgary and have a uncorked BRP. The altitude is just over 3000 ft in Calgary.

I use a 170 main. You must buy part # 16012-MBN-641 B53E needle (in the 3rd clip position for most of Alberta). The 68S should be perfect for most of Alberta as well.

Use these charts to help you jet for your altitude! http://www.xr650r.us/jetting/

This site http://xr650r.us/ is great and will help you with your BRP.

I am in Cold Lake. The elevation here is about 1500 ft. Yeah, I used a hole saw to cut out the intake manifold. I am also running a B53E in the 3rd spot, but I used the existing seat, should I have put in the new seat as well? I didn't notice a difference between the two.

The popping is very minimal and I have to really be on the gas first then cut the throttle before it pops.

[Chopp]

I was playing with the fuel screw and it is popping a lot more on deceleration....so I think I can get it to a managable level by fiddling around with the fuel screw some more...

Edit - it hardly pops at all now with the fuel screw at 2.5 turns out...

[slotcarrod]

Happy you got it sorted out.?

I think the seat is the same but I put mine in. I got a few different main jets + - for different temps and riding altitudes. If I were you I would drop your main to a 172. I run a FMF Ti pipe that is a little more flow and I still would run a 172 at your alt. Just my 2 cents!

[Thumpage]

I was playing with the fuel screw and it is popping a lot more on deceleration....so I think I can get it to a managable level by fiddling around with the fuel screw some more...

Edit - it hardly pops at all now with the fuel screw at 2.5 turns out...

Chop,

As a note; You shouldn't have to be more than 2 turns out on the fuel screw under normal circumstances with the correct size pilot jet. With the correct size pilot jet, your fuel screw setting should fall somewhere from 1.5 turns to 2 turns out.

The 68s pilot jet might not be quite rich enough for your current tempurature so this may be one reason why the bike is running lean. This is most likely why you might be having to set the fuel screw past 2 turns.

The needle position might be slightly lean also for this time of year up there. I think you could get away with not having to go through the trouble of changing the clip position though.

For a reference to properly tuning the fuel screw, go back to the Pigpen website, to the facts page, http://www.xr650r.us/xr650r_faq/. Under 'fuel system' click on the #6 question and you will find a short paragraph on how to tune the fuel screw. After doing this, it should give you the indication of whether the 68s is too small at this point. If it is, you can choose to step it up or simply live with turning the fuel screw past 2 turns to try and help compensate to some degree for the meantime.

[zx7rye]

Mine is setup for SM...popping on decel was pretty noticeable. I set mixture to 3 turns out (going in 1/4 turn increments from the stock 2 turns) and voila! I also attribute alot of the popping to low 30 degree temps and very dry air. Summer will probably be a bit different.

[motopsycho650]

Where are you in Alberta?

You did not say if you cut out or replaced the rubber intake manifold in front of the carb. This is a must! If you are not good with a Exato knife and Dremel sp?, here is the number for the Carb Insulator # 16211-MBN-640.

I am in Calgary and have a uncorked BRP. The altitude is just over 3000 ft in Calgary.

I use a 170 main. You must buy part # 16012-MBN-641 B53E needle (in the 3rd clip position for most of Alberta). The 68S should be perfect for most of Alberta as well.

Use these charts to help you jet for your altitude! http://www.xr650r.us/jetting/

This site http://xr650r.us/ is great and will help you with your BRP.?

Honesly, I hate that jetting chart. It makes the pig seem so damn picky when it comes to temp & altitude. I ride between 5000-10000+ ft. in Colorado.

My engine is stock. I run the HRC intake, HRC needle (4th notch), and the HRC spark arrestor. I use a TwinAir Power-Flow kit and have the cut out side panel. Even in my altitude, I'm jetted with a 170 main, and a 70S pilot jet. I bought a T-handle adjustment screw from www.carlscycle.com and have it around 1.25 turns out @ 5000 Ft. For higher elevation, or as my air filter gets dirty, it needs 1/8 - 1/4 of a turn leaner.

Before the cutout side panels, I ran a 68S pilot, and a 168 main. The pilot adjustment was set to 2 turns out @ 5000 Ft. Again, only a 1/8 - 1/4 turn learner was required for altitude changes.

I don't understand why I'm higher in altitude, in an area with little to no humidity, and have my bike set up with richer settings that a lot of other people here. I've played with my setup a lot! Trust me, my bike's power is maximized for it's equipment.

[slotcarrod]

I have a few buddies that drag race at a pro level. They are always talking about the air, barometric pressure, density, temp ect. They even have weather stations in the trailers.

On a pro level you need to tune for your "air". If we are just playing, get it in the ball park and have fun. If you are racing and want the most from your bike, buy a bunch of jets.

[Chopp]

I am going to order maybe a 70s and a 172 main just to play around with and see where that takes me...

[Chopp]

Yeah this thing runs like a scared cat! I have been out a lot lately since the weather is great. I can't believe the power this thing has. It pulls good on the road, but when you hit the dirt the power seems more noticeable. This bike has almost gotten away on me a couple times on the trails!! The rear tire hooked up solid when I was expecting it to spin and the front lifted like a rocket ship and I barely hung on! It sure cruises nice over fast trails as well.

All in all very nice machine and I am pretty happy I got this monster.

Now I just need to tune the CRF150F so it runs a little better....