Dynorun on my WR450

[Wheeliedevil]

Took my bike to work yesterday and put it on the dyno. I havn't seen any numbers before but I guess that this is pretty good for a WR450? I've compared it with KTM's 525 with akrapovic complete system and that bike "only" produced 48hp. Also a Honda XR650 with high komp piston, flatslide, hotcam, complete exhaust ... That bike produced 52 at wheel..

I had some trouble to get the bike run smooth at midlerange and steady gas at "cruising-throttle-position" say 1/8. I suspected a few things. The YZ camshaft, the dyno-needle that is a stage 2 WR needle and not for the YZ (I didn't plan to change the camshaft until I read about it in here), My AP mod witch is a complement between my own theory and redbeards. But I solved the problem within an hour and here's the result....

[renthal1]

Wow thats pretty impressive

[Wheeliedevil]

Thanks! ?

Anybody has numbers af a stock derestricted bike?

My mod's for this are:

* Opened air/box, standard hole behind the battery, on left side behinde the airbox cover there are two marks in the air box, one of them is like a triangle and the other one is like square. I cut these open and back with the cover. On left side I had to open up the whole side. I only left about 1cm around to attach K&N filters precharger in the cover so the airbox wouldn't be wide open. Note that this bike is going to run 95% as a supermoto and this mod may not be reccomended for dirtriding only!! Ofcourese I placed prechargers over the othe openings aswell.

* K&N air/filter

* Dynojet 4150 stage 2 for Wr 05-06 (never mind the year, it's the same, mine is a -04!) Needle goes as far down as possible, circlip in frist groove. DJ160 (note that the DJ main jets does NOT use mm's like kehin does, so a keihin 160 is much smaller than a DJ160 plus that the DJ's needs an adapter (inkluded in kit)). mixture screw is adjusted to 13,5 A/F, pilot jet #48.

* AP-mod, shorten the rivit from 3mm to 1,5 and place a greased (for longer life) O-ring over the AP linkage to make the squirt more instant and the o-ring flex after the throttle reaches 75%. That's where the ap now stops working. 50% is standard.

* Ported cylinderhead.

* Kibblewhite stainless valves and springkit. This has nothing to do with the power. It's standard size. I did a leak-down test and one of the stock exhaustvalves leaked pretty much so to prevent this I bought this "kit" This will also make the valves last much longer than the std titanium. It's possibly that the stock valves (if they would have sealed properly) would have made the bike produce even faster hp's becourse they are lighter and only has one spring (this kit has two due to more wheigt/valve).

* YZ 450 -04 exhaust camshaft

* Stock header and a own-made slip-on with a shortened Akrapovic sliencer from a Honda SP-1

This is my recepy to an insane ride. Enjoy! ?

[odonnks]

WOW--- real impressive.

You say you adj. the a/f to 13.4. I assume that was with a O2 sniffer up the pipe. If so, at which throttle position did you adjust for? It seems neat impossible to adjust a flat a/f number accross the entire range of the throttle.

Thanks

[Wheeliedevil]

Yep, I had a o2 sensor to help me out. That's the whole idea with the dyno. I would never had this power/response if I would have to guess it on the street. This whole adjustment took me about 2 hours and that inkluded cutting some holes in the airbox aswell.

It's correct that I adjusted the air fuel to 13,5 on the mixture screw. AT IDLE. That is the only point that the mixture screw does anything. If you start to lift the throttle you also starts to use the pilot jet, then the needle and emolusion tube and finally at top main jet.

So my adjustment to 13,5 with the mixture screw was at idle and nothing else. I didn't count how far the swrew went, I only looked at the screen and adjusted. That's why I only wrote this. On a carb it's not easy to have a flat a/f curve, that's correct. It's far more easy to tune a fuelinjected bike with a powercommander ?

[Moto5]

Thanks for sharing, those are some great looking numbers.

[Wheeliedevil]

Ofcourse! ?

I'd be glad to help you guys out if I can!

[TimBrp]

Impressive for sure. Weird thing is I just got my Cert. of Origin and it states 59HP on it. I was like &%$#@!???

[Wheeliedevil]

And "my Cert. of Origin and it states 59HP" means?? ?

Sorry, I'm swedish ? Don't know all terms...

EDIT: I guess that this is the certificate that you get with your bike that tell that it is your's?? And on it, it says how much HP you bike produces, right? It would be interesting to se how much it produces on the dyno. Anybody who knows?

[odonnks]

I've been think about using a exhaust sniffer my self. We have a bunch of portables here at work.

Questions: Why 13.4/1 ?

Isn't the a/f of 13.4 a little rich? I've always been told optimum stoichiometric mixture is 14.7 to 1 (sea level). As altitude increases OR temperature increases the Air mixture should increase.

Thanks again

[Wheeliedevil]

No it's not rich. When we map bikes at work we set the cruise A/F to (depending on bike) from 13,5 up to 13,7 and powermode (above a certain rev and about 20% gas) to 12,8 up to 13,2. This is also what dynojet recommends so I don't think that it's just here in Sweden. When not using turbos or other overcharging this is what's recmommended for bikes.

It's different between cars and bikes. Cars runs much leaner than bikes probably becourse there are much more cars and the pollutionrestrictions are very hard from that industry. I have a Subaru impreza with some mods and I also have a widebandcommander also from dynojet in that car that tells me the realtime a/f. When I cruise the car uses it's factorys closed loop map and that is 14,7 or lambda 1. That's so lean that I can feel it. When I hit the gas and the boost comes on it goes down to around 12. That is mapped into the unichip that I use to controll fuel, ignition, boost... That's becourse it needs so much more fuel just to cool down the engine or I would melt the pistons. I also built myself a RepsolHonda RC211V-replica turbo. That bike also had 12.0/1 at max boost. You have to to to keep it in one piece!

[odonnks]

Thanks,

You also mentioned that you opened the air box more than just removing the under seat snorkle and the two side panel cutouts.

I've often wondered if just the snorkle and cutouts are enough. I know it depends on the pipe. The only way I know to test is with a manometer across the box and carb inlet throat. That's not an issue. The problem I have is trying to get a reading under engine load. I don't have access to a dyno and trying to read it while riding would likely cause an accident.

Were you able to compare the differences between the 'typical' air box mods and the extras you did?

I always thought Lambda was used as a a/f term when more than one type of fuel was used.

Thanks again

[OlaGB]

Great results wheeliedevil!

Last summer i called up a dyno-company in norway, to see if someone had been testin theire wr450 there.. Two guys had been there, one stock 03` and one pipe`d 03`.. Think it was a davinci mufler..

If my RAM memory is working right, hehe, then the stock one made 48HP and the piped one made 53.. RWHP that is of course.. They didnt know about any other mods done to the, since they only write the most important specs on the dyno sheet..

[wedrivezs]

I thought it was 12.5?

[Wheeliedevil]

I thought it was 12.5?

Excuse me? What did you think was 12,5?

[Wheeliedevil]

Thanks,

You also mentioned that you opened the air box more than just removing the under seat snorkle and the two side panel cutouts.

I've often wondered if just the snorkle and cutouts are enough. I know it depends on the pipe. The only way I know to test is with a manometer across the box and carb inlet throat. That's not an issue. The problem I have is trying to get a reading under engine load. I don't have access to a dyno and trying to read it while riding would likely cause an accident.

Were you able to compare the differences between the 'typical' air box mods and the extras you did?

I always thought Lambda was used as a a/f term when more than one type of fuel was used.

Thanks again

It's very tricky to cut in the airbox without a dyno. I hade made about 10 25mm holes in the left side cover from the beginning. Then the bike produced 49hp's and was very nervous at even throttle/cruising. Removed the cover completly and cut two holes on the oter side behind the cover. Putted back the cover and seat so the bike would act as it was ment to be driven. Then It made 52 but it was still nervous. I had to lower tha needle maximum to get it to stop being nervous. Now keep in mind that this was a Dynojet stage 2 needle. Designed for opened air-box.I didn't have a snorkle from the beginning in my bike. We don't have restrictions in our bikes in sweden. I also loaded the dyno to get the street feeling. I tryed up to 40% brake to simulate driving. I did this while "developing" the correct jetting. This was also how I noticed the nervousity at even throttle.

There was no way that I could have made a "typical airbox mod" to gain this power. I could have used smaller jets but then I also had to change back the needle to stock. But Then I would lose power. If you can add more air to a rich engine it will produce more power. Within some limits ofcourse, you also have to get it inside of the engine.

I've only worked with lambda with regular pumpgasoline.

[Wheeliedevil]

Great results wheeliedevil!

Last summer i called up a dyno-company in norway, to see if someone had been testin theire wr450 there.. Two guys had been there, one stock 03` and one pipe`d 03`.. Think it was a davinci mufler..

If my RAM memory is working right, hehe, then the stock one made 48HP and the piped one made 53.. RWHP that is of course.. They didnt know about any other mods done to the, since they only write the most important specs on the dyno sheet..

Ok. thanks alwas good to know. I bought this bike last fall after driven it for 10min at the company that I work. About a week after that I fell pretty bad with a bike and crushed a few bones in my foot and broke three other bones so I've done this mods while healing. That's why I didn't put it on the dyno before...

[odonnks]

You pretty much answered my question. From a modded air box to a more modded air box you gained 3 hp. I had suspected that even with the snorkle removed and the 'template' cutouts removed from the right side that there was still some restriction from the box. Re installing the right cover after doing the cutout seems like a step backward.

I'm not sure what the best way to allow the box breath and not permit debris from entering but I did see these that looked like a good solution.

http://www.rockymountainatv.com/productDetail.do?prodFamilyId=6786&navTitle=Intake&webCatId=16&pageLinkUri=&vehicleType=&webTypeId=177&navType=type

I'm gonna toy around with the O2 analyzer and air box mods a little.

You've provided EXCELLENT info... Thanks a bunch !

[Wheeliedevil]

You pretty much answered my question. From a modded air box to a more modded air box you gained 3 hp. I had suspected that even with the snorkle removed and the 'template' cutouts removed from the right side that there was still some restriction from the box. Re installing the right cover after doing the cutout seems like a step backward.

I'm not sure what the best way to allow the box breath and not permit debris from entering but I did see these that looked like a good solution.

http://www.rockymountainatv.com/productDetail.do?prodFamilyId=6786&navTitle=Intake&webCatId=16&pageLinkUri=&vehicleType=&webTypeId=177&navType=type

I'm gonna toy around with the O2 analyzer and air box mods a little.

You've provided EXCELLENT info... Thanks a bunch !

Yes, becourse my bike could accept more air at that point. That doesn't mean that I can throw away my whole airbox and use even larger jets. That's what I mean by "the bike can accept more air/fuel" It has to get it in the engine too. That's why turbo is invented ? The turbo only blows air into the engine and to that you add as much fuel as needed due to boost. A very nice invention. Works good on bikes too.. Check out the one I built at: http://www.sporthoj.com/forum/showthread.php?t=27772&highlight=rc211v+uppdatering

This is "stage 2" I used fuel injection at "stage1". What's more updated is the paintwork to match Valentino Rossis RC211V new paint for that year. There are a few pics as the pages goes by but the complete bike is at page 4 and 5. The forum's in swedish but just ignore that..

I actually saw those airbox vents on my friends new bike today, actually. Don't really think they are a good solution. I use K&N filters pre-chargers instead. Check them out here: http://www.knfilters.com/wraps.htm

I buy a large one and cut it to make it fit and then glues it in the airbox. I'm going to do that to the sidecover too, I'm just out of it right now. Have to order more. They will let air but not dirt inside the box plus that you also have the filter inside the box. I uses K&N filter too. http://www.knfilters.com/dirt_bike.htm

For MX bikes they uses 4 layers of woven premium cotton media allow for increased filtration.

Thanks for listening! ? Just let me know if I can help you out in any way.

[wedrivezs]

Excuse me? What did you think was 12,5?

optimum air fuel