Help! I adjusted KLR valves, now no start

Discussion in 'The Garage' started by socalscott, May 10, 2018.

  1. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    So I adjusted valves on my KLR 650. Same basic idea as the many toyotas, motorcycles and vw's I have done. Strange thing is, before disassembly I verified tdc and when crank was on the 'T' mark, cam lobes were pointing inward, not outward as the clymer manual shows. Rotated crank several times, still was in same position, cam lobes pointing inward, marks on timing gear not lining up with top of head. So I put it back together the 'right' way, 'T' mark lined up, piston at top of cylinder. Cam gear marks just above flush with head. After several attempts, finally got it started, died as soon as I let go of throttle. Took it back apart, checked tdc, maybe a tooth off on cam gears. Readjusted, so marks lined up with top of head. No start at all now! Getting frustrated. How did it run before with cam gear marks way off while crank was at the 'T' mark? Don't want to line it up 'wrong' the way it was before just because it ran that way. Any help would be greatly appreciated. Thanks in advance
    #1
  2. Beezer

    Beezer Long timer

    Joined:
    Oct 26, 2004
    Oddometer:
    8,318
    Location:
    Anchorage, formerly Spenard (hub of the universe)
    the T is always in the window at TDC, but there are 2 TDCs, one is exhaust. at TCD, the exhaust cam lobes MUST point forward, the intake lobes must point aft. cam marks should be parallel to the head, but might be off a bit but thats OK.... changing a tooth makes it worse. I never bother with the T... I find TDC and look at the cams. be sure to remove the chain tensioner during the process, and re-set the tensioner prior to installation.

    is this a Gen I or II? makes no difference for the timing but I used to do tech days and have a few tips, especially for the Gen I
    #2
  3. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    Beezer, thanks a bunch for the info. So with cams off, the piston at TDC doesn't care if it is compression stroke or exhaust, as the cams are what dictate this, is that correct? So as long as piston is at top of stroke and cam lobes are pointing outward, marks lined up, I should be ok? When I got it started, I played with the idle stop screw to try to keep it running, can you tell me where to set it to get me in the ballpark? Thanks again for the help. Very much appreciated.
    #3
    Beezer likes this.
  4. Bindlestiff

    Bindlestiff Been here awhile

    Joined:
    Aug 5, 2013
    Oddometer:
    175
    Location:
    PNW and Montana
    Yeah, the cams will be pointed out on one TDC and if you rotate the crank 360 degrees they'll be pointed in. I believe KLRs have a "waste spark" ignition system that fires at TDC on both the compression and exhaust strokes, so if you took the cams off and reinstalled them exactly 180 degrees off it should be fine.

    So, when you're trying to get the bike to run, how are you giving it fuel? Are you putting the tank back on? The vacuum petcocks on these bikes are notoriously finicky. I'd definitely check to make sure the lines are hooked up tight and in good shape. If you're putting gas in the carb some other way, make sure the vacuum line is plugged.
    #4
    socalscott likes this.
  5. Beezer

    Beezer Long timer

    Joined:
    Oct 26, 2004
    Oddometer:
    8,318
    Location:
    Anchorage, formerly Spenard (hub of the universe)
    yes SS.... sounds like you got it figured out on the cams. as for the idle stop screw, it should set low RPM at about 1200-1300... you just have to fool with it. set it when the engine is fully warmed up and the enricher off. have you done the "22 cent" mod? thats where the needle is shimmed up with 2 washers (22cts worth), the slide id drilled (don't bother with that), and the idle MIXTURE screw is set. the factory sets the mix as lean as it will run and then pounds a little plug in over the adjusting screw. you have to drill a small hole in the plug & pull it out. then seat the adjuster, then back the adjuster out 2 to 2 1/2 turns. heres a thing on the CV/CVK...

    http://vulcangadgets.com/files/keihin_carb.html

    the CV on the Harley shares only a few parts with the CVK... its a different casting to accommodate the accelerator system. whenever changing jets be sure you know whos jets you are using because Kehin (Kawaisaki) is a different set of numbers than Dynojet

    as mentioned above, the petcock can be a problem. check the vacuum line.... any trace of fuel is bad, it means the diaphragm leaks. it will pull extra fuel past the carb. it can also fail in such a way that no fuel gets to the carb

    if you pull the carb off, be really careful with the enricher cable, its tricky to get threaded right & easy to break. pull it on full to remove/install, that compresses the spring so you don't have to fight it. also, if you get the opportunity, remove the 2 Phillips type screws that hold the manifold boot to the head. replace them with Allen heads or (my favorite) the case bolts with the 8mm heads. then you can pull the manifold and carb as one unit.... much easier than fighting the 2 rubber boots

    let me know when you want to do the forks... they need help. I used to run KLR tech days
    #5
  6. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    Thank you both for the info. Bindle, I just put tank and vacuum/fuel lines, on without reattaching fan or bolting up coil. I tried today after 3rd time adjusting timing and still no go. Smells like it is flooding after trying to start it for a bit. Checked spark, seems fine. Then I put a thumb over a compression tester hose screwed into spark plug hole as I rotated crank, when i felt a slight 'pop' after removing my thumb, I rotated crank until I hit tdc mark just slighlty after, assuming I was on compression stroke. When I took valve cover off, both cams were pointing inward. Left it at 'T' mark, flipped cams so lobes are pointing out and arrows were just slightly above level with head. If I went one more tooth, I am sure the arrows would be below level with head. Havent tried starting it yet, need to torque cams and put tank on. Fingers crossed! I will find out tomorrow. You guys are a great help. Thanks so much!
    #6
    Beezer likes this.
  7. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    This really got me thinking after still no success today. I checked fuel tank and it was well above the 'reserve' tube and about 1/2" from top of the 'on' tube. So I hooked up a vacuum gauge and applied vacuum, bam! No flow on reserve or on position! So I tried sucking through using lung power and nothing, just felt completely closed. So now I realize, I probably had it right the first time I got it running and the vacuum petcock just happened to fail on me. Got one on the way for a Raptor. Thanks so much once again for all the help. I will keep you posted.
    #7
  8. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    Well, I was not applying vacuum to the vacuum line, but the fuel line, oops! Petcock seems fine. I rechecked valve clearances, and right exhaust valve was zero clearance. Strange, since I checked it twice before ordering shims and it was way looser than spec. Got the correct shim on the way, I am hoping that takes care of it and she will be up and running. Thanks again for all the help!
    #8
  9. whisperquiet

    whisperquiet Motorcyclist

    Joined:
    Aug 24, 2007
    Oddometer:
    1,750
    Location:
    62298 in lovely corrupt/bankrupt Southern Illinois
    #9
  10. Bindlestiff

    Bindlestiff Been here awhile

    Joined:
    Aug 5, 2013
    Oddometer:
    175
    Location:
    PNW and Montana
    In general, the valves being out of adjustment won't cause a no-start on its own. It might make it hard to get it to stay running, but it should show some sort of signs of life when you try to start it. More commonly, if the bike won't start after a valve adjustment it's because something got jostled or broken while taking the bike apart to get to the valves. I mentioned the petcock as a likely suspect, but I recall it's also easy to pull a wire off the coil while you're getting the valve cover out from under the frame. The plug wire can also degrade such that the wire can pull slightly out of the boot on the plug or on the coil. Before you put it completely back together, I'd definitely give the bike a once-over to check for pulled-out or loose wires or hoses. (Of course this is all assuming you're sure you've got the cams back in the correct position.)

    Also, since you didn't explicitly mention this: you just adjusted the valves as routine maintenance, right? The bike was running fine before?
    #10
    socalscott likes this.
  11. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    Yep Bindle, was running fine before. I made sure to follow the clymer manual, so I'm wondering what went wrong. I did get it started twice, but it would not stay running without throttle. That's when I decided to take it apart again thinking I was close, but maybe a tooth off. It did sound fine though other than not idling. I checked spark, got a blue spark. I got shim coming in today. I hope to get it back together and try again. It seems if I get the intake cam marks lined up perfectly with head, exhaust is either arrow pointing slightly up, or just below head surface. I counted 45 teeth from pin above mark to the other pin above mark per Marks diagram so I wonder if I need to pull carb next. I've done many valve adjustments so I am feeling stupid now. Thanks again for the help
    #11
  12. larryboy

    larryboy Chopper Rider

    Joined:
    Jan 9, 2005
    Oddometer:
    20,700
    Location:
    Über Alles,California
    Sounds like bent valves.
    #12
  13. Beezer

    Beezer Long timer

    Joined:
    Oct 26, 2004
    Oddometer:
    8,318
    Location:
    Anchorage, formerly Spenard (hub of the universe)
    the marks almost never align perfectly.... it should be fine. carb.....
    #13
  14. Beezer

    Beezer Long timer

    Joined:
    Oct 26, 2004
    Oddometer:
    8,318
    Location:
    Anchorage, formerly Spenard (hub of the universe)
    larrboy posting same time as me.... bent valves..... maybe. does it pop or backfire.... make any weird noises when it does run?
    #14
  15. anotherguy

    anotherguy unsympathetic

    Joined:
    Jun 18, 2009
    Oddometer:
    10,361
    Location:
    the hills
    A too tight valve or two will cause hard starting. As will a malfunctioning decompressor. Verify clearances and inspect the decompressor spring condition for starters.

    In addition to that it needs 3 items to run. Fuel,spark and squeeze. Check the obvious before panicking.
    #15
    socalscott likes this.
  16. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    Beezer, would having cams 180 out cause valves to bend? It ran fine before i did adjustment. I hope I didn't damage something from trying to start with timing off... when i first tried to start it, it backfired but it sounded fine when it finally did start.
    #16
  17. Beezer

    Beezer Long timer

    Joined:
    Oct 26, 2004
    Oddometer:
    8,318
    Location:
    Anchorage, formerly Spenard (hub of the universe)
    I agree.... check valve clearances. KLR valves get tighter over time. if you have a clearance that got bigger then ya... possibly bent valve that is not closing... usually in pairs, like both exhausts. I only remember seeing one, once that got tighter but it was only a thou or 2. a valve thats bent enough to make it not run usually has some bad engine popping, wheezing or other odd noise. one of our tech days some years ago a guy left a paper towel in the chain tunnel... fired the bike up & it ran great for about 15 seconds & then the towel got into the chain and made it jump. bike would not start. we re-set the cams & it ran fine. it had another 10k miles on last I saw it years later. but.... yes, if it was really off, the piston will hit the valves. you can see dents in the piston where the valves hit if you have a scope
    #17
    socalscott likes this.
  18. socalscott

    socalscott Adventurer

    Joined:
    May 21, 2014
    Oddometer:
    17
    Location:
    menifee California
    Got her running and she purrs like Eartha Kitt! Thanks guys for all the help and awesome info. Exhaust valves at .026 mm and .025, intakes are .020 and .018, new plug. Runs very smooth and quiet. You guys all rock!
    #18
    larryboy likes this.
  19. vagueout

    vagueout Long timer

    Joined:
    Mar 3, 2010
    Oddometer:
    3,020
    Location:
    sydney, east
    Am i missing something here ? like wtf was causing the problem?:*sip*
    #19
    socalscott likes this.
  20. anotherguy

    anotherguy unsympathetic

    Joined:
    Jun 18, 2009
    Oddometer:
    10,361
    Location:
    the hills
    Yeah what he said..........cannot leave us hangin'!
    #20
    socalscott likes this.