Thanks to Jim Hyman, who provided this write-up. He originally posted it to the DSN KLR650 mailing list on 11 December, 2001.
N.H.T.S.A. - the National Highway & Traffic System Administration has NOT issued a recall, but they should.
If you've been the victim of a balancer system failure, contact NHTSA and file a formal complaint. Keep in mind that they deal with ANY safety related concerns for all vehicles.
Sudden engine lockup certainly qualifies as a safety hazard.
For newbies: Don't have a hissy fit! The balancer problem is rare but it should NOT be ignored.
In the 20 months that I've been a part of this list, the balancer thread has reared its ugly head several times when a lister had a problem. There is usually a collective yawn from the list on this topic, with only a half dozen or so listers expressing any interest. Elden Carl (KLR guru) has championed against the balancer system's weak points for a long time. Check out the messages at the Yahoo/KLR web site on August 31, 2000 for an in-depth discussion on KLR mechanicals - the good, the bad & the awful. I can email an unedited version of all the messages in TXT or ms-word DOC format to anyone interested.
The balancer system is self adjusting AFTER you have manually loosened & re-tightened the balancer adjuster bolt. All KLRs from 1996 (A10 models) on have an "improved" balancer adjuster setup, but there have been several failures with the IDLER LEVER on the newer systems.
ADJUSTER BOLT TOO LOOSE: The idler lever may move so that the balancer chain is too loose. A loose balancer chain will cause more engine noise from the lower left side of the engine.
ADJUSTER BOLT TOO TIGHT: The idler lever may be deformed & won't self adjust in the future when you try to adjust the balancer. This is primarily a problem with the A9 & earlier models. Recently several listers have reported problems with their A10 (1996) & newer model KLRs.
At 19K miles, I had to remove the outer rotor cover [visual method #1] & manually move the balancer's idler lever almost 1/2" (11 mm) toward the front of the engine to remove the excess slack in my KLR's balancer chain. The "standard" balancer adjustment procedure did nothing to quiet the noise from the engine's lower left engine case. This method can be used to confirm if the balancer's spring is working or not. Excess chain slack is difficult to diagnose using this method. You can't inspect either of the balancer levers for potential problems using this method.
DON'T use a 3/8" ratchet for the adjuster bolt. A 1/4" ratchet or extension bar will give you a much better feel. Tighten the bolt to finger tight and then tighten 1/8 of a turn further. This will give you the proper 52 - 69 INCH-pounds of torque (i.e. 4 - 6 FOOT-pounds)..
TENSIONER SPRING BROKEN OR MISSING: You won't be able to properly adjust the balancer and there is no way for you to know that there is a problem unless you remove the rotor/magneto and both left side engine rotor covers.
ONE OR BOTH BALANCER LEVERS BROKEN OR CRACKED: You must remove the inner & outer rotor covers, along with the rotor to visually inspect the full balancer system. [visual method #2]
Several listers have expressed (misplaced) pride in the fact that they haven't done any KLR maintenance for many 10's of thousands of miles & everything is just fine. BULLSH*T!!! I've worked on too many bikes for too many years and seen too much damage from neglected maintenance.
WHAT CAN YOU DO? Kawi calls for balancer adjustments every 3k miles, or 5 km. Perform the adjustment at least this often. If you're the paranoid type, do the adjustment every 2k miles (3 km) or if there is abnormal engine noise from the balancer area on the engine's lower left side.
Visual method #2 (removing the rotor & both covers on the engine's left side) is the only way to confirm that you don't have a potential problem.
Follow Elden's procedure that was detailed in the "summer
spectacular show" on August 31, 2000:
1) fully warm up the engine
2) lean your KLR to the RIGHT side
3) loosen the balancer adjuster bolt 1 turn
4) tap the adjuster bolt with a light to moderate tap
5) retighten the adjuster bolt
If your engine is noisy on the lower left side and the balancer adjustment doesn't quiet things down, do the visual adjustment method, by removing the outer rotor alternator cover and if necessary, remove the rotor and the inner rotor cover for a thorough inspection of the balancer mechanism.
Professor A9 Federal Way, WA. [USA]
p.s.: email me
with details of your balancer system failures &
National Highway Traffic Safety Administration web site
Click on "complaint form" to report a Vehicle Safety Problem. This is from the "complaint form" page:
In order for NHTSA to respond promptly to requests for information, suggestions or comments; they should be addressed to: email@example.com.
Use this form only to report a problem. If you prefer, call the DOT Auto Safety Hotline at 1-888-DASH-2-DOT (1-888-327-4236) and a NHTSA representative will record your report. Your report will be entered into NHTSA's vehicle owner's complaint database and used with other reports to determine if a safety-related defect trend exists.
If a safety-related defect exists in a motor vehicle or item of motor vehicle equipment, the manufacturer must fix it at no cost to the owner. Your report is the first step in the process.
Government engineers analyze the problem. If warranted, the manufacturer is asked to conduct a recall. If the manufacturer does not initiate a recall, the government can order the manufacturer to do a recall.
We do not have to receive a set number of reports before we look into a problem. We gather all available information on a problem. Your report is important to us.