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Discussion Starter · #1 ·
Hi there! I just bought a 1987 KLR 650 and it has some trouble cold starting. I was aware that many KLR’s can be temper mental when it comes to cold starting but i’d love to be able to get it going without using any throttle. I have tried full choke, half choke etc. i have cleaned the carb, air filter, and put in a new spark plug as well. It has fresh gas in it as well. When I cold start it I have to use full choke and then give it gas. It sounds like it wants to start with no gas but simply won’t. I attempted to use the choke adjustment but I wasn’t sure if it was doing anything. At times I have to adjust the idle screw in the carb to even get it to idle for it to warm up. Otherwise I have to hold it at quarter throttle to keep it from dying on me until it warms up. I’d love to figure this out since it would be cool to start it up normal with the choke and not have to use throttle. The bike has 30,000 on the speedo. It looks really well kept and i’ve also done quite a bit of work to it since I bought it. Anyone got any pointers on what may be going on? I have not touched anything else on the carb except the idle screw on the outside of it. Another thing worth noting is that if the bike is set to full choke and I give it some throttle while trying to start it fires up very quickly. Even when it’s cold. The problem is no matter what I do it will not start without the choke on full and throttle. It’s also worth mentioning that after it’s warmed up it starts no problem without the choke and throttle.
 

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Another thing worth noting is that if the bike is set to full choke and I give it some throttle while trying to start it fires up very quickly.Even when it’s cold. The problem is no matter what I do it will not start without the choke on full and throttle. It’s also worth mentioning that after it’s warmed up it starts no problem without the choke and throttle.
You are describing the classic symptoms of 'Low Compression' at start up because of Too Tight of Valve Clearance, especially on the RH Exhaust valve which has the KACR (Kawasaki Automatic Compression Release) on its cam lobe.
Compression specs with an active KACR are 77 - 124 psi with Wide Open Throttle.
Opening the throttle creates More Cold Cranking Compression.

With a clean engine & spark plug pocket, I recommend you perform a WOT CCC test to see what it currently has.
Then measure valve clearance, adjust all to the upper half of specs. Then perform another WOT CCC test to how much was gained.

You might ought to look & see if the air filter has been passing dust due to lack of oil or a split seam. This causes rapid valve & seat wear, as well as piston. ring & cylinder wear, which attributes to low compress and excessive oil consumption.
 
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Also get et the carb out and check the carb enrichment circuit for clogs, also make sure the choke is functioning properly, there should not be a lot of slack in cable.
 

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Discussion Starter · #5 ·
You are describing the classic symptoms of 'Low Compression' at start up because of Too Tight of Valve Clearance, especially on the RH Exhaust valve which has the KACR (Kawasaki Automatic Compression Release) on its cam lobe.
Compression specs with an active KACR are 77 - 124 psi with Wide Open Throttle.
Opening the throttle creates More Cold Cranking Compression.

With a clean engine & spark plug pocket, I recommend you perform a WOT CCC test to see what it currently has.
Then measure valve clearance, adjust all to the upper half of specs. Then perform another WOT CCC test to how much was gained.

You might ought to look & see if the air filter has been passing dust due to lack of oil or a split seam. This causes rapid valve & seat wear, as well as piston. ring & cylinder wear, which attributes to low compress and excessive oil consumption.
I guess you were right. Compression reading it gave me was around 45psi. That’s way too low. So what’s the process to fix this?
 

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2013 KLR 650/692, 2017 HD Electraglide Ultra
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First, adjust the valves to the LOOSE end of the spec. Intake spec is .004-.008”. Exhaust is .006-.010”. Then as PDW said, recheck CCC at WOT. Search this forum for more details as we have discussed this many times and recently.
 

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Discussion Starter · #7 ·
First, adjust the valves to the LOOSE end of the spec. Intake spec is .004-.008”. Exhaust is .006-.010”. Then as PDW said, recheck CCC at WOT. Search this forum for more details as we have discussed this many times and recently.
So I just have a few questions. I don’t know much about valves. When you say loose does that mean the largest number (meaning the largest clearance? And is this done with those shims or is there just an adjuster?
 

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Discussion Starter · #8 ·
So I just have a few questions. I don’t know much about valves. When you say loose does that mean the largest number (meaning the largest clearance? And is this done with those shims or is there just an adjuster?
Another thing to note is I found a leak on the engine head gasket I believe. It’s right under the cylinder head. There’s a lot of oil there that I hadn’t noticed before because of the fairings. Could that be the source of the leak?
 

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You need to change the shims for proper ones(thinner ones), valve clearance usually gets tighter, valve seat wears so the valves are not sealing(they are staying a tiny bit open). Exhaust valves are usually most affected. First You need to measure valve clearance with cold engine at TDC, then calculate which thinner shims You need to get to obtain the proper clearance. The oil is probably seeping from head cover gasket, not the head base gasket? When You do the valves check the gasket, if it is intact add a tiny bit of engine sealer on it all the way around.
 

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2014.5 KLR650
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Lots more similar threads if you scroll to the bottom of the page too ...
 

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So I just have a few questions. I don’t know much about valves. When you say loose does that mean the largest number (meaning the largest clearance? And is this done with those shims or is there just an adjuster?
Your posting tells me that as a bare minimum, you need to purchase a Clymer service manual for your 1987-2007 KLR650, about $38.00 and read the pertinent sections & procedures.

Do you have any/many basic Metric hand tools?
Bare minimum, you will need to purchase a 1/4" drive torque wrench calibrated in Inch Pounds with about 40 -200 inch pound range and a 15 blade feeler gauge set from .0015" to .015" and understand how to use them.

Or possibly better yet, take your bike to a professional shop before you make an expensive error. Maybe the previous owner already made a semi-expensive error which may be causing the oil leak. A professional shop should know how to best assess a possible issue.
 

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2013 KLR 650/692, 2017 HD Electraglide Ultra
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As PDW said, get a Clymer manual. It’s easy to cause yourself more trouble if you don’t have the 3T’s—tools, talent, and time. A repair manual is the most important tool in your toolbox.

It’s great to learn to maintain and repair your own equipment, and the experts here willl help you. What previous mechanical experience do you have? What tools do you have?

Read this thread: DPelletier's common new KLR owner mistakes to avoid
 

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2014.5 KLR650
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I’ve got a 1st Gen Clymer, new, you can have it for $20. and the shipping, but I’m in Canada so the shipping might be a deal breaker ...
 

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Discussion Starter · #14 ·
I’ve got a 1st Gen Clymer, new, you can have it for $20. and the shipping, but I’m in Canada so the shipping might be a deal breaker ...
When I bought the bike it actually came with a Clymer manual for it!
 

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Well ... OK ...
 
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