07 WR450 Unsolvable :(


22 replies to this topic
  • westdot

Posted November 12, 2013 - 04:24 AM

#1

Right, i have Google searched for about a month and tried pretty much everything to get this bike running without any luck. I bought the bike it had been sitting, cleaned the carb etc got it running except it was bogging, turned out it was the acel pump spring, so i got a new one and managed to tune the bog out. The bike has an FMF pipe, the acel stop has been removed and the air-box snorkel has been removed, AIS removed. I sent the bike for a service as i was going for an enduro ride in Victoria Falls. The service included a new battery, oil, oil filter, air cleaner and tires. The enduro was amazing until the final day the bike died about 20km from the finish :( The bike coughed and spluttered a bit then died completely. I notice allot of oil on my swing arm and boot so further investigation showed that an old repair on the crank case had come off and oil was leaking out as well as oil was coming from the air-box. This made me think i had seized it, but i was confused as the bike still turned over but would not start. 2 weeks later finally get round to looking at the bike, i repaired the old crank case hole, and though i would drain what oil that remained in the bike and put new oil. To my surprise 1.5 liters of oil came out, this for one is too much i normally put 1,1 liters, and this 1.5 doesn't include the amount that came out during the enduro or left in the engine as i drained it cold. Anyway the people that serviced it clearly over oiled it. This explains the oil coming out the airbox via the breathers. So bike turns over and there is still oil, to me means cant be seized. So i tried to start it and after a few kicks it started, had to keep the revs high to stay on but sounded good, no knocking it just wouldn't idle at all. So this let me to believe it was the carb. Another 2 weeks passes by I try starting it again and nothing at all, a few backfires. So i service the carb thoroughly and the bike still wont start. So i think it is timing now, i checked the timing and all ok( i have set it before so i know how) and nothing. So now i think ok it must be electrical. I removed the spark plug and put it against the chassis and there is a nice blue spark, also tried a different plug in the bike and still no joy just the occasional backfire, it will also not bump start. I also redid the entire wiring harness checking all connections, earths, insulators etc. didn't help. I have tested , my ignition coil in an 04 wr450 and it worked fine. So we have fuel, we aslo have spark so now i think its compression. I check the valve clearances and this is what i found : My manual says my intake clearance must be .1-.15 and exhaust .2-.25 My exhaust were .127 and .178 and my intake were .178, .229 and .254 So this was a Saturday and no shops open and a real urge to ride on Sunday i decide to swap the current shims around and see what i can do. This is what i managed: exhaust .229, .229 and intake .178, .254 and .127 Put the head back on connected the carb and battery and hey it started (exhaust and airbox ware off completely) so excited i put the entire bike together, and it wont start :( about 50 kicks later it starts, its ideling high let it warm for a bit and go for about 300 meters and its running as normal, no strange noises and good power. Then it died and no matter how much i kicked it would not start, about 3000 kicks at least. This was last weekend and have not done anything since then. Have a sore leg from the amount of kicking haha. I know that 2 of the intake valves are still out but they are loose not tight, is this the problem or have i missed something, i am really tired of this problem whatever it may be....... Any comments or questions are welcomed...

  • Yamaguy55

Posted November 12, 2013 - 05:18 AM

#2

If it will start every time with starting fluid (ether) it is usually ( emphasis on "usually") carb/fuel related. That is the quick cheating way to separate what is doing what. If you have spark at the right time, plug is good/new, no crud on plug wire/cap, and have good compression, then it has to be fueling or valves/valve timing. I'd be sure carb didn't have something in the pilot circuit. In theory, that and the choke/enrichening circuit are all that are in play to start the bike. Needle/slide and main are only for larger throttle openings. So every jet/ passage for pilot circuit needs to be proven to be working correctly. If valves were tight, are any messed up? Burned, not properly seating? I had an FZR for a time with the tight valve problem and until I got that resolved, it would have a tough time starting and then only run at higher RPM. Once the valves were straightened out, it ran great.
Do a compression check if valves are suspect.

How much of the oil in the air box got into the carb and clogged things up?
This will no doubt be simple, you just have to find it.

Follow all of the carb setup stickies above. Your problem is most likely related to at least one of them.

Edited by Yamaguy55, November 12, 2013 - 05:21 AM.


  • Krannie McKranface

Posted November 12, 2013 - 06:25 AM

#3

You need to remove the carb and inspect it fully.

You made no mention of replacing the now contaminated air filter...

More than likely, you have oil/debris in the air jet and pilot jet.....

While you are at it, replace the plastic nut on the top of the hot start (cracks, leaks) and inpect the plunger for good seal.



  • Bandit9

Posted November 12, 2013 - 02:30 PM

#4

Yeah my instincts are screaming clogged pilot. That damn pilot has a way of getting clogged the day after cleaning it......

  • grayracer513

Posted November 12, 2013 - 03:47 PM

#5

If the intakes are loose, then there are a limited number of reasons for that.  You could have valves held of the seat by carbon at the valve stem or close to the valve face, excessive wear at the cam caps, "mushroomed" or broken off valve stem caps (an integral part of the valve itself), or bent valves. 

 

One way to account for the excess of oil is water in the crankcase.  If you stalled in a stream crossing or some such and failed to pull the breather out of the water before attempting to start it, you may have pumped a half quart of the river into your engine.  In that case, there is usually something "wrong" with the way the oil looks.

 

Water could explain the carb, too.



  • westdot

Posted November 13, 2013 - 02:04 AM

#6

Thanks for the reply's.when i serviced the carb I made sure all jets /passages we blown out with compressed air, i can assure you it is clean. maybe as bandit9 said it might have got re-blocked by some unbelievably bad luck. I hate taking the carb of this bike as it involves taking the whole sub frame off. Krannie sorry forgot to mention but I did cleaned the air filter and air-box,re oiled the filter with air filter oil. none of the valves look burnt, i am reluctant to take the head of as to get another head gasket is not to easy for me as i live in Zimbabwe and spares have to be imported from South africa which can take weeks. the hot start is removed on my bike and the hot start hole has been blocked. Surely if this was the problem the bike would run crap when it did start? i don't understand why the bike runs smooth and has good power when it does run. The oil when i drained it looked fine, it did not have water mixed with it (no milk-shake). Also during the ride there was minimal water, very hot and lots of dry river beds.

  • Krannie McKranface

Posted November 13, 2013 - 07:29 AM

#7

If your battery is not perfect, it will not start, even with the kicker.



  • Bandit9

Posted November 13, 2013 - 08:20 AM

#8

That is true, experienced this myself. Nice thinking Krannie.

  • mattfidaho

Posted November 14, 2013 - 08:35 AM

#9

when the carb was cleaned do you know if any carb cleaner was used? or soaked? hot bath?

I had similar issues with mine when I bought it, it had apeared some one along the road, (probably the guy trying to get it ready to sell after sitting so long) had soaked the carb and caused cracked seals deep inside.

after a full rebuild of the carb, and all seals she runs great.



  • westdot

Posted November 15, 2013 - 02:19 AM

#10

The battery is brand new, but i will jump start it from my car and see if it starts.. What are symptoms of a faulty cdi? how do i check if the spark timing is ok..?

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  • Krannie McKranface

Posted November 15, 2013 - 06:20 AM

#11

The battery is brand new, but i will jump start it from my car and see if it starts.. What are symptoms of a faulty cdi? how do i check if the spark timing is ok..?

You can't.

 

If you have spark, move on.



  • grayracer513

Posted November 18, 2013 - 10:28 AM

#12

You can check spark timing with a strobe, although it can be a messy enterprise.  The flywheel has a pair of marks located to the left of the TDC mark, often called the "H" because it consists of two radial marks joined by a short horizontal line.  At idle, and (I would assume, but don't know for certain) at cranking speeds, these marks should appear aligned with the mark in the upper inspection hole of the flywheel cover. 

 

The messy part is if the engine starts and crankcase "respiration" starts belching oily mist out the hole. 

 

If the timing is off, it's generally a faulty CDI, as the timing is not adjustable.  Another possible source of timing error could possibly be a faulty or misadjusted TPS, but you can check that by disconnecting it and trying the timing check again.



  • still2smokin

Posted November 19, 2013 - 12:12 AM

#13

I had a very similar electrical gremlin. Ran great for a half mile or so then would bog and back fire then die and I could not get it started again for a few hours or days.

 

When I would test for spark it would fire every time but still not start.

 

In the end and after many new parts ...... it was the connector going to the

spark plug. 

 

The plug was completely corroded away. 

 

IMG3056_zps1887e792.jpg

 

I cut it off and made my own temp plug and it ran great then I

ordered a new wiring harness .

 

 



  • grayracer513

Posted November 19, 2013 - 09:31 AM

#14


In the end and after many new parts ...... it was the connector going to the

spark plug.

 

I cut it off and made my own temp plug and it ran great then I

ordered a new wiring harness .

 

It should go without saying, but save the old harness as a source of emergency replacement connectors.



  • westdot

Posted November 19, 2013 - 11:17 PM

#15

Thanks for the reply's, will check those today and get back to you. Thanks

  • DeepPurplishBlue

Posted November 21, 2013 - 05:35 PM

#16

I had a very similar electrical gremlin. Ran great for a half mile or so then would bog and back fire then die and I could not get it started again for a few hours or days.

 

When I would test for spark it would fire every time but still not start.

 

In the end and after many new parts ...... it was the connector going to the

spark plug. 

 

The plug was completely corroded away. 

 

IMG3056_zps1887e792.jpg

 

I cut it off and made my own temp plug and it ran great then I

ordered a new wiring harness .

 

 

Had the exact same problem with a 2005 WR450...   except on this one the plug showed no obvious signs of trouble.

Visually it looked brand new, unlike the one in the picture above.  That looks like a couple years under the sea!  

 

After exhausting every other possibility with no change in the symptoms we decided it had to be the plug and forced

extra wire in it so it fit tighter on the ignition coil.   The bike lit up instantly and ran like a raped ape.   Unbelievable

amount of time wasted chasing that gremlin.  A bit surprising that multiple examples of this are popping up.  Had

never heard of these plugs failing before and I have many other WRs with heaps more hours and miles on them than

this bike.

 

For the permanent fix I cut the plug off the wiring harness salvaged from a scrapped bike and soldered it in.   Works great,

and as grayracer said save the old harness, there is a lot of value in having those connectors and wires available to make

repairs such as this!



  • grayracer513

Posted November 22, 2013 - 10:58 AM

#17

All gang connectors of this general sort have some built-in means of removing the individual terminals (the metal socket or pin/blade part on the end of the wire lead) from the body of the connector.  The exact method of removal, and even the question of which end of the connector the terminal is inserted or removed from, varies from brand to brand (harness connector brand, not bike brand) quite a bit, and can even be different from one connector to another on the same harness, but it generally involves inserting some sort of pick, thin blade, or similar tool into the connector to depress a small metal tang on the terminal and allow it to exit.   Can be tricky to figure out, but doing that can let you steal a terminal from one connector on an old harness and use it in a different one on the harness being repaired.

 

GM dealers usually stock all kinds of harness repair parts, mostly for use by their own service departments.  You can pick up individual brand new terminals, connector bodies, connector seals, etc. to repair a harness in one of their cars.  I think it's fairly likely that at least some Japanese auto dealers would do the same thing, and may carry parts compatible with the WR harness.  Just another avenue to explore.



  • woods-rider

Posted November 22, 2013 - 11:04 AM

#18

If your battery is not perfect, it will not start, even with the kicker.

 

I kick-started my 2006 many many times when it had a dead battery that wouldn't' turn the motor over. Kicking works just fine.

 

 

 

The battery is brand new, but i will jump start it from my car and see if it starts.. What are symptoms of a faulty cdi? how do i check if the spark timing is ok..?

You can't.

 

I have also jump started my 2006 multiple times and my 2012 once from a 12v car battery when the bike battery was drained. It worked just fine.


Edited by woods-rider, November 22, 2013 - 11:07 AM.


  • Krannie McKranface

Posted November 22, 2013 - 01:48 PM

#19

  Dead battery is different from a bad battery. A bad battery is usually an open cell = open circuit.



  • westdot

Posted November 29, 2013 - 07:05 AM

#20

I checked the conector for the spark plug, it looks  good, i dismantled the conector and checked each terminal and both look good and connect snug onto the coil back terminals. I finished shimming the bike and all valves in spec now. The bike will start sometimes but then die after a few mins. Then start it again and it dies after a few mins.anyway i give up now and accept defeat :( havn't riden for a month now :( taking the bike to a shop on monday.


oh and with the battery connected or disconnected the symtoms are the same.






 
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