I want to make my bike a monster. Need help


19 replies to this topic
  • mikeythefokker

Posted March 20, 2011 - 05:37 PM

#1

I currently own a very tired 07 wr450, and next year I am taking it to baja. To the bikes credit I have never been into the motor at all, and it still runs well, but it's just a little tired. My overall goal is to get 5 to 6 more horsepower out of the bike, and have a bike that can go 100mph, and be reliable. I'm going to be doing a new top end(OEM piston) and I am going to be putting yz cams in. I want more power from my bike, mostly to be able to run taller gearing and still have some grunt down low. High compression pistons and any mods that require race gas are out, because in baja you take whatever gas you can get. I don't think that a big bore kit is what I want either because I like the reliability of stock yamaha parts. I'm mostly curious about what people do in terms of head work and porting? I'm not looking to go to crazy, but I would bet there are 3 or 4 extra horsepower hiding in that head. I'm also curious about valves and valve jobs. Is there any power to be gained there without sacrificing reliability. I know that some people advance timing a degree or 2 as well, and I am also curious about vertex ignitions and whether there is anything to be gained there. My wr has been a great woods bike for me, but now that I have my 2 stroke I get to build more of a dedicated higher speed/ desert bike and I'm excited about it.

  • tribalbc

Posted March 20, 2011 - 05:50 PM

#2

Well I had my head flow ported this winter, while I was getting seats cut and new OEM valves installed.The machine shop claimed a 3-5 hp gain, they specialize in Yamaha heads.
I can't really comment on the changes yet as I've only rode less than 15min sorting out jetting and light break in. I also changed a few things around, from YZ cams to YZ intake, WR exhaust, and a new pipe. Put in same HC piston I had in previous, but as you said you don't want to go down that road with Baja gas.

  • mikeythefokker

Posted March 20, 2011 - 07:38 PM

#3

Let me know how that works out tribal. How much did you raise your compression? Does your starter still work or do you have to kick it now?

  • tribalbc

Posted March 20, 2011 - 08:01 PM

#4

Let me know how that works out tribal. How much did you raise your compression? Does your starter still work or do you have to kick it now?


13.5-1 compression. Runs fine on 91+ pump. Last year I had that same piston, YZ cams and a YZ exhaust. Estart was 50/50 at best, and it took a ritual. That's why I went with the WR exhaust cam this time, to try and retain my reliable estarting. I only tried estarting once in the limited time I've had it running now, and it didn't fire, but jetting is still not 100%.
Jetting with the YZ cams and HC piston wasn't very far off the mark of previous jetting, a hair leaner. But this combo of flow porting and a Jardine exhaust system, has me going way richer. It's also cold out right now, and I'm not quite there....

  • mikeythefokker

Posted March 20, 2011 - 08:41 PM

#5

13.5-1 compression. Runs fine on 91+ pump. Last year I had that same piston, YZ cams and a YZ exhaust. Estart was 50/50 at best, and it took a ritual. That's why I went with the WR exhaust cam this time, to try and retain my reliable estarting. I only tried estarting once in the limited time I've had it running now, and it didn't fire, but jetting is still not 100%.
Jetting with the YZ cams and HC piston wasn't very far off the mark of previous jetting, a hair leaner. But this combo of flow porting and a Jardine exhaust system, has me going way richer. It's also cold out right now, and I'm not quite there....


F>CK. I hope it's the piston that's giving you trouble. I really don't want to lose my button. What year yz cams did you use, and did you do both of them or just the exhaust? I've heard conflicting reports on whether the yz and wr intake cams are the same. I've also heard that the 06 bike was supposedly the "fastest" and had the most aggressive powerband so I was looking in that direction. I'm just getting started with this, so sorry for all of the pain in the ass questions. Who did your head, and what exactly did you have done?

  • tribalbc

Posted March 21, 2011 - 06:39 AM

#6

F>CK. I hope it's the piston that's giving you trouble. I really don't want to lose my button. What year yz cams did you use, and did you do both of them or just the exhaust? I've heard conflicting reports on whether the yz and wr intake cams are the same. I've also heard that the 06 bike was supposedly the "fastest" and had the most aggressive powerband so I was looking in that direction. I'm just getting started with this, so sorry for all of the pain in the ass questions. Who did your head, and what exactly did you have done?


08 YZ cams, like I said, last year, I used both intake and exhaust, this year I'm only using the YZ intake. Originally I had planned on only doing the YZ intake. I had heard YZ intake, HC piston was the hot ticket to good gains with reliable estart. YZ and WR intakes are different.
But since I scored both cams together for $100, cheaper than just an intake, I tried them both. Gains were great, super easy kickstarting, but ureliable estart. I'm pretty sure I'll get my estart worked out no problem now with the WR exhaust cam. The problem is the YZ exhaust has too long a decompression pin, dumping too much compression for estarting.
The other option is the hot cams, if you're paying retail for YZ cams the hot cams are no more expensive, and they have the shorter decompression pin on the exhaust cam for reliable WR estarting.
Mongoose Machine, here in Vancouver BC did the head work. They are the top small engine (bikes, snowmobiles) machine shop here in western Canada.
I had my valve seats cut with new valves,seals and springs installed.
My head was flow ported, the most intensive kind of porting, measuring flows for gains. You provide your intake boot and exhaust header for them to run the "flows" They had some cheaper options of just cleaning stuff up as well.

If it really warms up later this week (doubtfull) I'll be able to give her a real run and let you know what I think. But more likely, I'm back to work for 2 weeks (shift work, out of town) at the end of this week. So when I get back early April I'll be able to really wring her out see what she's got :thumbsup:

  • mikeythefokker

Posted March 21, 2011 - 05:09 PM

#7

Yes, please let me know how it all works out for you. I'm a few weeks away from digging in. So you live up in BC? I thought it was all forests and tight woods riding u there. Where are you going to use all that power? Ha ha.

  • tribalbc

Posted March 21, 2011 - 05:21 PM

#8

Yes, please let me know how it all works out for you. I'm a few weeks away from digging in. So you live up in BC? I thought it was all forests and tight woods riding u there. Where are you going to use all that power? Ha ha.


Endless hillclimbs :thumbsup:

And I've got the 2 stroke now for the tighter stuff, might as well unleash the beast :bonk:

  • ARin

Posted March 23, 2011 - 08:47 AM

#9

As someone who just came back from a week in baja, my recommendations are to leave the motor stock. Spend your money on a bigger fuel tank and a better headlight.

I was down in baja with a group of 70 (split into smaller rider groups ~10 people per), and the general consensus seems to be "if you want to rock, leave it stock". I checked my valves, jetted for sea level, and didnt touch anything else on my 04.

I was geared stock up front and 46 in the back, and it seemed a perfect balance between top speed and still plenty of low end power. baja is a LOT of 4th gear riding...just lazy (but fast) trails mixed in with single track sections and short sections of sand and quick jaunts on the asphalt. Of course, this will all be dependent on how your trip is coordinated.

Folks with stock fuel tanks were constantly fiddling with gas bottles, or borrowing from other bikes. Folks with crappy stock headlights had trouble seeing if they got stuck out too late. people with modified bikes had reliability problems. KTM's burnt up on the cortez-side sand, Hondas threw rods and locked up on the freeways, the one Husaberg and the other Husky just seemed like they fell apart the entire time.

Whatever you decide to do, pack light, and have fun.

Posted Image

  • Gunner354

Posted March 23, 2011 - 03:14 PM

#10

I currently own a very tired 07 wr450, and next year I am taking it to baja. To the bikes credit I have never been into the motor at all, and it still runs well, but it's just a little tired. My overall goal is to get 5 to 6 more horsepower out of the bike, and have a bike that can go 100mph, and be reliable. I'm going to be doing a new top end(OEM piston) and I am going to be putting yz cams in. I want more power from my bike, mostly to be able to run taller gearing and still have some grunt down low. High compression pistons and any mods that require race gas are out, because in baja you take whatever gas you can get. I don't think that a big bore kit is what I want either because I like the reliability of stock yamaha parts. I'm mostly curious about what people do in terms of head work and porting? I'm not looking to go to crazy, but I would bet there are 3 or 4 extra horsepower hiding in that head. I'm also curious about valves and valve jobs. Is there any power to be gained there without sacrificing reliability. I know that some people advance timing a degree or 2 as well, and I am also curious about vertex ignitions and whether there is anything to be gained there. My wr has been a great woods bike for me, but now that I have my 2 stroke I get to build more of a dedicated higher speed/ desert bike and I'm excited about it.



The wr has been clocked at 100mph stock.
I found out the hard way while 5th gear pinned. Tail swopping at that speed was not fun. Knocked out, two broken ribs and a broken coller bone. Considered myself lucky!

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  • mikeythefokker

Posted March 23, 2011 - 05:26 PM

#11

I topped mine out at 88 with the stock gearing. It was also screaming its lungs out by 70 and I don't like abusing it like that. My goal of getting the bike to do 100 isn't really because I want to go 100, its more that I want to be able to do 75 without breaking a sweat, and in stock form, that ain't happening. I've also ridden my bike with the stock front sprocket and a 48 rear and it didn't feel good.

  • Gunner354

Posted March 23, 2011 - 06:30 PM

#12

I topped mine out at 88 with the stock gearing. It was also screaming its lungs out by 70 and I don't like abusing it like that. My goal of getting the bike to do 100 isn't really because I want to go 100, its more that I want to be able to do 75 without breaking a sweat, and in stock form, that ain't happening. I've also ridden my bike with the stock front sprocket and a 48 rear and it didn't feel good.


I think your speedo may be wrong

  • CanadianWR450

Posted March 25, 2011 - 01:22 AM

#13

I'm running a athena 480 big bore, hotcams, SS megabomb/Ti powercore along with all free mods.

40 hours on it now, and not a single hiccup, e-start works perfect, and it starts on one kick hot or cold.

15/48 gearing, monster bottom end/torque, and it will pull pretty much any gear, anywhere. I don't know what gear I'm in half the time.....it could easily pull higher gearing

Power delivery is VERY smooth and woods friendly (I know your talking baja though)...

Know you were not looking at big bore, but just some thoughts for ya.....

  • tribalbc

Posted March 26, 2011 - 08:44 PM

#14

Well I can give a limited ride update, still haven't really put it through a real ride test, but as least the jetting was right.
WR exhaust cam has taken out the "hit" and some top end pull (still haven't really ran full throttle very long)
Flow porting has just given it more grunt all over, what I was told it would do by the techs.
So basically the power is smooth and really strong, excellent low end grunt. With a low idle, not touching the throttle, it will walk up a decent incline and not want to stall :ride:

So first impressions are it feels really awesome and strong, but a little bit vanilla..... I might go back to the YZ exhaust cam for that little mid hit and more top end, but then there goes the estart again and some low end....

When I get back and do some real riding in 2 weeks, I'll give you the full report, very limited ride so far. It's now broken in and ready to rip :thumbsup:

But IMO right now is it a 100mph dirtbike :bonk:
Not feeling it. I had a true 100mph dirtbike in the past, a 97 Husaberg FE501, and I still don't think this WR had the juice that baby did. But hopefully I'm proven wrong....

  • mikeythefokker

Posted March 26, 2011 - 11:56 PM

#15

I'm running a athena 480 big bore, hotcams, SS megabomb/Ti powercore along with all free mods.

40 hours on it now, and not a single hiccup, e-start works perfect, and it starts on one kick hot or cold.

15/48 gearing, monster bottom end/torque, and it will pull pretty much any gear, anywhere. I don't know what gear I'm in half the time.....it could easily pull higher gearing

Power delivery is VERY smooth and woods friendly (I know your talking baja though)...

Know you were not looking at big bore, but just some thoughts for ya.....


Hey thanks for the input. I'm not really looking for the big bore mostly because of the money. I am also afraid that a big bore could make my bike tougher to jet, less reliable, and possibly run hotter. However, I don't really know much about them, so my fears could be totally unfounded and unfair. If my cylinder needs to be re plated then i would look into one. 15/48 sounds like exactly what I want to be running though, and that power is going to have to come from somewhere.

  • mikeythefokker

Posted March 27, 2011 - 12:00 AM

#16

Well I can give a limited ride update, still haven't really put it through a real ride test, but as least the jetting was right.
WR exhaust cam has taken out the "hit" and some top end pull (still haven't really ran full throttle very long)
Flow porting has just given it more grunt all over, what I was told it would do by the techs.
So basically the power is smooth and really strong, excellent low end grunt. With a low idle, not touching the throttle, it will walk up a decent incline and not want to stall :ride:

So first impressions are it feels really awesome and strong, but a little bit vanilla..... I might go back to the YZ exhaust cam for that little mid hit and more top end, but then there goes the estart again and some low end....

When I get back and do some real riding in 2 weeks, I'll give you the full report, very limited ride so far. It's now broken in and ready to rip :thumbsup:

But IMO right now is it a 100mph dirtbike :bonk:
Not feeling it. I had a true 100mph dirtbike in the past, a 97 Husaberg FE501, and I still don't think this WR had the juice that baby did. But hopefully I'm proven wrong....


Did you play with the yz cam at all( advancing it a degree or 2) to see if you could get the e start to work? A few other guys seem to have made it work. I sure as hell don't want to end up with a kickstart wr. Also, how much did the flow porting run you? If you don't want to put it out there you can PM me. I'm just curious. Need to get my budget and plan ahead. Thanks again Tribal.

  • CanadianWR450

Posted March 27, 2011 - 02:08 AM

#17

Hey thanks for the input. I'm not really looking for the big bore mostly because of the money. I am also afraid that a big bore could make my bike tougher to jet, less reliable, and possibly run hotter. However, I don't really know much about them, so my fears could be totally unfounded and unfair. If my cylinder needs to be re plated then i would look into one. 15/48 sounds like exactly what I want to be running though, and that power is going to have to come from somewhere.


Mine is a 04, and the stock gearing was 15/50.
I think your 07 may be different though, but as mentioned mine could easily run higher gearing.
Jetting - ended up being pretty much exactly what the JD instructions say to use for a WR 450. The cams/exhaust = a bit richer, while the big bore = a bit leaner which over all, has cancelled each other out.
Overheating - none for me at all, while I'm certainly not in Cali or baja, I do a lot of slower woods riding with less airflow.
Reliability - all I can say is that I have 40 hours on it with no issues, but I'm also certainly not racing, nor does it see the rev limiter (or even high rev's) much as with the power/torque it has now, it doesn't need too....just shift up a gear instead of wringing it out....it can pull the next gear easily and still keep the rev's down.

Understand about the $$. I needed piston and to replate anyway....cost ended up being only $70 more for big bore then OEM/replate.

  • mikeythefokker

Posted March 27, 2011 - 10:03 PM

#18

If I need a replate, then the big bore will probably happen. The 70 bucks is probably worth not having to wait for your cylinder.

  • tribalbc

Posted March 28, 2011 - 05:36 AM

#19

Did you play with the yz cam at all( advancing it a degree or 2) to see if you could get the e start to work? A few other guys seem to have made it work. I sure as hell don't want to end up with a kickstart wr. Also, how much did the flow porting run you? If you don't want to put it out there you can PM me. I'm just curious. Need to get my budget and plan ahead. Thanks again Tribal.


It's not the timing thats the problem, the YZ decompression pin is too long. If your looking for that extra top end and are worried about estart, I would just go with the Hot Cams option.
Flow porting runs around $400 CAD, sure you would get it a fair bit cheaper in the US.....

  • tribalbc

Posted April 23, 2011 - 10:20 PM

#20

Well finally got to take the WR on it's first real test ride today at the MX track. Definately a ton of torque. I could pull a gear higher in the corners no problem, and not have to touch the clutch. This is compared to my bike last year which had YZ cams- exhaust and a HC piston.
Very smooth with heaps of power, lacking a bit of snap, very old world big bore feeling. I'm sure the YZ exhaust cam would fix that right up........
Should be good power for the woods, it makes it's most meat in the bottom to mid, and like I said it has a ton of grunt of idle. Went for a putt with my son on his bike today in the pits, and could just cruise around with no hand on throttle or clutch, even with a low idle :thumbsup:
Kick starting is a 1 kick affair, maybe 2 if cold. Estart works, but labours a few revolutions, I think due to the high compression piston. I also only run the small 2.5A Ebatt battery. But with a stock WR motor this fires her right up. But battery is also over 2yrs old now and got drained this winter......




 
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