• Announcements

    • Bryan Bosch

      JUST IN!   04/24/2018

Sign in to follow this  
Followers 0

WR Camshaft Swap Info


List of 5-Valve OEM Camshafts & Part Numbers

Year  Model          WR Intake Cam    WR Exhaust Cam   YZ Intake Cam    YZ Exhaust Cam   Comments1998  YZ/WR400F      5BF-12170-00-00  5BF-12180-00-00  5BE-12170-00-00  5BE-12180-00-00  WR exhaust cam advanced 1 tooth1999  YZ/WR400F      5BF-12170-00-00  5BF-12180-00-00  5BE-12170-00-00  5BE-12180-00-00  WR exhaust cam advanced 1 tooth2000  WR400F/YZ426F  5BF-12170-00-00  5BF-12180-00-00  5BE-12170-00-00  5BE-12180-00-00  WR exhaust cam advanced 1 tooth2001  YZ/WR426F      5BF-12170-10-00  5BF-12180-01-00  5BE-12170-10-00  5BE-12180-01-00  WR exhaust cam advanced 1 tooth2002  YZ/WR426F      5BF-12170-10-00  5BF-12180-01-00  5BE-12170-10-00  5BE-12180-01-00  WR exhaust cam advanced 1 tooth2003  YZ/WR450F      5TA-12170-00-00  5TJ-12180-10-00  5TA-12170-00-00  5TA-12180-00-00  Same intake cam. WR exhaust cam advanced 1 tooth2004  YZ/WR450F      5TA-12170-00-00  5TJ-12180-10-00  5TA-12170-00-00  5TA-12180-00-00  Same intake cam. WR exhaust cam advanced 1 tooth2005  YZ/WR450F      5TA-12170-00-00  5TJ-12180-10-00  5TA-12170-00-00  5TA-12180-00-00  Same intake cam. WR exhaust cam advanced 1 tooth2006  YZ/WR450F      5TA-12170-10-00  5TJ-12180-20-00  5TA-12170-10-00  5TA-12180-10-00  Same intake cam.2007  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-30-00  5TA-12170-20-00  5TA-12180-20-002008  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-30-00  2S2-12170-00-00  2S2-12180-00-002009  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-30-00  2S2-12170-00-00  2S2-12180-00-002010  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-30-00  N/A              N/A2011  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-30-00  N/A              N/A2012  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-40-00  N/A              N/A2013  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-40-00  N/A              N/A2014  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-40-00  N/A              N/A2015  YZ/WR450F      5TJ-12170-00-00  5TJ-12180-40-00  N/A              N/A

Cam specs
Per 2grimjim's post, all 03-09 YZ OEM cams have identical lifts & duration. The only difference is the lobe centerline angle (LCA). Lobe Separation Angle (average of intake and exhaust LCA) is listed as LSA. Intake & Exhaust durations are listed @.050" lift.

Cam           Intake LCA Exhaust LCA   LSA      Intake Lift  Exhaust Lift  Intake Duration  Exhaust Duration  Comments03-05 YZ      109°       104°          106.5    8.61mm       8.43mm        244°             244°              Same intake cam as 03-05 WR/04-05 YFZ.  Exhaust LCA NOT measured. Calculated exhaust LCA by assuming YZ exhaust cam is WR cam retarded by 22.5°06 YZ         106.5°     104°          105.25°  8.61mm       8.43mm        244°             244°07 YZ         Unknown08-09 YZ      102.5°     99.5°         101°     8.61mm       8.43mm        244°             244°03-05 WR      109°       126.5°        118.25°  8.61mm       8.43mm        244°             244°              Same intake cam as 03-05 YZ/04-05 YFZ06 WR         106.5°     126.5°        116.25°  8.61mm                     244°                               Same intake cam as 06 YZ.  Exhaust LCA NOT measured. Calculated exhaust LCA by assuming WR exhaust cam is YZ cam advanced by 22.5°07-11 WR      107°       113.5°        110.25°  7.65mm       7.75mm        236° (@.040")    236° (@.040")03-04 HotCams 105°       105°                                                                                 http://www.thumpertalk.com/topic/56257-yz-450-cam-mod-please-read/page-31#entry775865HotCams       110°       103°          106.5°   8.86mm       8.67mm        269° (@1mm)      265° (@1mm)       4023-1IN 4044-1E http://hotcamsinc.com/ProductInfo.aspx?item_id=574 http://hotcamsinc.com/ProductInfo.aspx?item_id=55904-05 YFZ     109°       127.5°        117.75°  8.61mm       8.43mm        244°             244°              Same intake cam as 03-05 WR/YZ

The WR exhaust cams open before BDC on the power stroke, wasting combustion power. Additionally, there is little to no overlap with the intake stroke, so the exiting exhaust gases do not help draw in new fuel during the intake stroke. More info http://www.thumpertalk.com/topic/264230-wr-to-yz-cam-timing-advantages/#entry2309905


The 2007-2015 WR intake cam has approximately 1mm less lift (~7.65mm) and ~20° less duration than the YZ cam. The 2007-2011 WR exhaust cam has approximately .68mm less lift (~7.75mm) vs the 03-09 YZ cam. The shorter lift contributes to the low-RPM power & lug-ablity of the 2007+ WR.




Varying the Lobe Separation Angle
According to Web Cam Racing-

As a general rule, tightening the LSA will:
  • Increase low-RPM torque
  • Create a narrower power band
  • Increase maximum torque

Widening the LSA will:
  • Raise high-RPM torque
  • Create a wider power band
  • Reduce maximum torque

Above 114° LSA = Extremely wide

112°-114° LSA = Wide

110°-112° LSA = Moderately Wide

108°-110° LSA = Moderate

106°-108° LSA = Moderately Tight

104°-106° LSA = Tight

Below 104° LSA = Extremely Tight


See http://www.webcamshafts.com/index_blank.html?pages/degreeing.html for further details


Decompression Specs
Per 2grimjim's post:

Model        Lift     Duration (@.010" lift)   Open (@.010" lift)   Close (@.010" lift)   Center of LiftYZ exhaust   1.63mm   124°                     30° ABDC             26° BTDC              84° BTDCWR exhaust   1.63mm   143°                     3° BDDC              40° BTDC              110° BTDCYFZ exhaust  0.84mm   79°                      28° ABDC             73° BTDC              111° BTDC

YZ Exhaust Cam Generations


Prior to 2003, the cam base circle is different than 2003+ years, and the camshafts lack the decompression pin
2003-2005 are identical, and have the most grunt
2006 has a nice balance between low-end & top-end power.
2007 shifts the power towards the top-end
2008-2009 saw a more restrictive exhaust pipe and the cam further shifted the power towards the top-end


For more info:


1998 through 2002
For 1998 through 2002 WR400F/426F's, you can simply rotate the WR exhaust cam one tooth clockwise to get YZ timing. For instructions, see MotoMan393's site here: http://motoman393.thumpertalk.com/tech/yztime.html


To get YZ timing and auto-compression, you can use a 03-05 YZ exhaust cam, but you may not use the original timing mark on the YZ450F exhaust cam. Re-shimming is required as the base circle is a different diameter. See the following links for more details:


2003 through 2006
For 2003 through 2006 WR450F's, the WR exhaust cam is advanced one tooth counterclockwise, but the decompression pin will be in the incorrect position to work correctly. A yz cam swap is required. 03-05 YZ cams are identical.


2007 through 2015
For 2007 through 2015 WR450F's,you can swap to a YZ cam.


Additionally, for e-start to work consistently, you will have to grind the decompression PIN. For grinding instructions, see here: http://www.thumpertalk.com/topic/1141940-wr450f12-how-to-grind-a-yz-cam-for-e-startability/


See n16ht5's post to see how you can retard the WR exhaust cam and keep e-start by grinding the decompression PIN.

Sign in to follow this  
Followers 0

User Feedback

There are no comments to display.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

  • Similar Content

    • By Brock granberg
      So I recently replaced my clutch basket with a Wiseco clutch basket. I am sure I put the basket together correctly as I followed the instructions on how o take off the old gear and put it on the new basket and then I followed my manual on putting in my new basket. I did nor replace anything but the basket! I still have the original plates inside and te hub and pressure plate. I put it all back together without the cover on top and I pulled the clutch and the pressure plate went out like it should but when I put the cover on and I put it in neutral and kicked it over, I pulled in the clutch and tried to put it in gear and it just stalled, almost like the clutch lever wasn’t disengaging the clutch! I adjusted my knob on the handle bar both ways as much as I could and it did nothing! I don’t know where else I can adjust it or what to do! Please help! Thankyou!
    • By Dmax
      So I thought I should create a new thread to dump my vlogs into for the few that do watch them.  If you didn't catch my vlogs from last year for 2017, check them out here -> 2017 NMA Series
      Season 2 is well underway for 2018.  This year I'll be racing the Open A class competing in both the NORCS and NMA off-road series as well as the Desert 100 and maybe some other races throughout the year.  If you got any questions or recommendations, lets hear them.  Enjoy!
      Northwest Off-Road Championship Series (NORCS)
      Northwest Motorcycle Association (NMA)  
    • By DirtHam
      Hi friends - 
      In the midst of a fork oil / seal replacement on my (new to me) 2006 YZ450F and I've run into a bit of a mystery.
      As I pull the lower caps off the rebound rod, I'm surprised to not find any "jam nut" or "lock nut" that I can tighten/loosen the cap against.  Although both the 2006 factory manual and all the guides I can find seem to reference this jam nut, neither of my fork legs has one, nor what would seem to be room for one on the threads.
      Further, I don't see it visible on the parts fiche between 2006 and 2009.  Finally in 2010 it shows up but not as an individually purchasable part.
      Out of some confusion/frustration I used some vice grips to hold the rebound rod and unscrew the cap.  I don’t think I’ve done any terminal damage but the struggle to make it work further convinced me this was not the way it was intended.
      Has anyone else found this same setup inside their own forks?  What’s the correct approach to remove/reinstall these without damaging the components in the process?  I'm tempted to cut some more threads to make room for a locknut, but I'm confused how it has apparently worked without a locknut previously, and figure I must be missing something.  
      A few pictures for your reference below.
      Thanks in advance!
      BELOW:  the non-disassembled fork leg, note no visible threads under cap

      BELOW:  The disasembled leg, with vice-grip battle scars.  Does anything look amiss here?  The adjustment rod barely peeks out.


    • By SoCalMX70
      BRAND NEW in the box, still shrink wrapped, white Clarke tank that I bought for my YZ last year. I was going to go with the all white look with retro red graphics, but later decided against it. My loss is your gain! These tanks retail for $240.00 brand new.
      No pictures... It is literally sitting in the box it was shipped in, still wrapped! It's a stock white tank. Here is a link to the info on it if you need it:
    • By Bryan Bosch

      Rockstar Energy Husqvarna Factory Racing Rally Star Earns Third Overalll at the 2018 Edition of the Event in Morocco
      April 20, 2018 – (Motor Sports Newswire) – Determined to wrap up his week-long adventure in Morocco on a high, Rockstar Energy Husqvarna Factory Racing’s Pablo Quintanilla has topped the fifth and final stage of the Merzouga Rally to secure a solid third overall in the event’s final overall standings. Continuing to make progress Andrew Short has claimed a spot inside the top 10 in the overall.
      Featuring a mass, motocross-styled start in the dunes of the Merzouga Desert, the fifth and final stage of the event saw Pablo Quintanilla put in a dominant performance. Posting the fastest time for the day, the Chilean rally star solidified his strong third position in the overall standings.
      Putting in his best individual stage performance Rockstar Energy Husqvarna Factory Racing’s Andrew Short crossed the line in eighth position. Wrapping up the Merzouga Rally 10th in the overall, the American is content with the progress he made during the week in Morocco.
      The Rockstar Energy Husqvarna Factory Racing Team will return to action at the third round of the 2018 FIM Cross-Country Rallies World Championship, the Atacama Rally in Chile on August 11/19.
      Pablo Quintanilla: “Today was a really fun stage. We had the motocross start and it was good to battle with the guys from start to finish. I got off to a good start but five or six kilometres into the stage I had a small crash that dropped me back a few positions. Then I had to push until the end and 10km before the finish I got the lead back and was the first to cross the finish line. It felt really nice to win a stage that way. Overall, I’m satisfied with my third position in the overall. This was a tough race with tricky navigation and to be on the podium is always good. We continue to gather experience and look ahead in the races to come.”

      Andrew Short: “I really enjoyed this week in Morocco. Especially this last day was really fun, bringing back memories from my days racing motocross. Before the flag dropped the nerves were there and I was maybe a bit late off the start. It was a good experience racing alongside the fastest guys in the dunes and being able to see their pace. The adrenaline kicked in and I had some really good fun. Overall, the week has been great for me. I enjoy the atmosphere in rally racing and I feel I am improving, getting closer to the top guys. I might still have a long way to go but I understand it needs to be done step-by-step. This week was a positive step in the right direction.”
      2018 Merzouga Rally – Stage 5 Provisional Classification
      1. Pablo Quintanilla (Husqvarna) 38:12 
      2. Kevin Benavides (Honda) 38:15
      3. Toby Price (KTM) 38:18
      4. Lorenzo Santolino (Sherco) 38:36
      5. Joan Barreda (Honda) 38:38
      6. Ignacio Cornejo (Honda) 38:54

      8. Andrew Short (Husqvarna) 38:56
      2018 Merzouga Rally – Final Overall Classification [Provisional]
      1. Joan Barreda (Honda) 13:28:19
      2. Kevin Benavides (Honda) 13:34:29
      3. Pablo Quintanilla (Husqvarna) 13:39:44 
      4. Franco Caimi (Yamaha) 13:47:08
      5. Ricky Brabec (Honda) 13:48:23
      6. Toby Price (KTM) 13:49:23

      10. Andrew Short (Husqvarna) 14:29:44
      Husqvarna Motorcycles. Tradition on two wheels since 1903.
      Husqvarna Motorcycles are widely known and respected in the off-road world for a heritage of competition and numerous motocross and enduro world championships. Originally founded in Sweden in 1903, Husqvarna Motorcycles have been designed and manufactured in Mattighofen, Austria since 2013.
      Rockstar Energy Drink
      Rockstar Energy Drink is designed for those who lead active lifestyles – from Athletes to Rockstars. Available in over 20 flavors at convenience and grocery outlets in over 30 countries, Rockstar supports the Rockstar lifestyle across the globe through Action Sports, Motor Sports, and Live Music. For more information visit: www.RockstarEnergy.com
      Source: Husqvarna Motorcycles GmbH