balancer chain break (rather long)

DSN_KLR650
Post Reply
Krgrife@aol.com
Posts: 806
Joined: Thu Apr 06, 2000 9:32 pm

balancer chain break (rather long)

Post by Krgrife@aol.com » Sat Jun 17, 2000 9:11 pm

I purchased my 91 A5 about 2 years ago and discovered this list shortly thereafter. I quickly learned that there had been an upgrade to the balancer mechanism in 96 but since my bike had only 14,500 miles on it I wasn't too worried. Last fall I picked up the new parts which consist of a new adjuster bolt that now has a washer on it and a larger flange in the middle so that it cannot be withdrawn through the case thus leaving the washer behind inside, I also got the new and stronger tensioner spring. I then delayed doing the install (you have to pull the alternator which takes Kawi's special holder tool) until I met Elden Carl in Mulege, Baja, last Thanksgiving. He described to me the problems that he had seen and urged me to change the parts and inspect the balancer when I got home. I still stalled a while until I got a call from another Baja riding buddy named Jim Bellach who lives in Kerman, Ca. His 93 KLR had only 18,000 miles and he had just started on a trip when his balancer chain broke stranding him on the highway. Jim is the guy who was delivering a parts bike to Elden at the Songdog-Cal Posse gathering. He is very maintenance oriented and was the first to tell me the importance of adjusting the balancer tension. This finally spurred me to get out the tool box last month and get busy. What I found was very disturbing. The old style tensioner bolt tends to distort the spring loaded lever arm that it goes through. Since this tensioner lever moves in a casting that conforms closely to its shape, when it is bent a little it no longer moves at all. This means that when you are doing the adjustment, loosening and retightening the adjuster, nothing is actually happening inside. That means the slack in the balancer chain increases until it finally lets go. My tensioner was at the outer limits of its effectiveness but I put in the new parts and got most of the slack out of it hoping that I had bought myself a few thousand more miles. I had already planned to do a top end rebuild later this summer and decided I would do the new balancer chain at the same time. I rode about another thousand miles and a week ago while out just putting around it let go. Jim's lever arm was bent just like mine and Elden says he has two or three more that are the same. The new bolt with the washer spreads the force over the face of the lever arm just enough to make the system work as it should. When the balancer chain lets go it typically locks up the engine and wipes out enough of the engine case that repair becomes incredibly costly. the engine casings are sold only as pairs at around $600.00. The balancer chain is $235.00. It also damaged the ignition trigger device that rides on the starter clutch gear behind the alternator and that is a $196.00 part. There are also chain guides and other miscellaneous parts in there that add up quickly. All this for want of a very small washer in the original design. I was fortunate to be going only about 35 mph about 1/2 mile from home and was able to grab the clutch quickly when everything locked up, as a result my engine case appears to be salvageable. I know that there are older KLRs like Conall's that have gone many miles with no problem, the thing is there is no way to know the condition of the tensioner system without opening up the left engine side, pulling the alternator and taking a look. I'm writing this not to start a debate on this problem but just to document what has happened to me and others. The thing that disturbs me most is if the engine had locked up while I was going around a curve at 70 mph--instant high side launch. I think about being in freeway traffic and having the engine lock up. Death is a real possibility. I now view this as a very real safety issue. My plan is to go ahead and spend the bucks to rebuild my engine before my fall Baja riding season begins, Elden has volunteered some good advice and I'm going to follow it with the goal of ending up with a bullet proof bike. I will admit that I didn't at first take Elden's advice too seriously, I even exchanged some off-list e-mails with Slide Lampson to that effect. I now retract all those opinions. Now that I have gotten to know Elden and realize that his opinions are based on solid observations and great mechanical insight and ability I'm going to avail myself of his advice and use the machine shops that he has confidence in. This means I will be hauling and shipping parts between Avila Beach and San Diego but since I'm down there monthly anyhow that is no problem. I'm going to document this whole process if there is interest and after the engine is done the suspension is also going to be upgraded. Part of this process also will be an upgrade of the clutch with the basket and parts from the later models. I bought my bike for $1700 with 14,000 miles on it and then put 20,000 more on before this happened, even with all that I will spend on repairs and upgrades I still feel it will be worth it. My bike will still look like a beater on the outside but where it counts it will be new or better than new. Plus this is going to be an interesting project and I expect to learn a lot, I'll keep you informed. Regards Kurt Grife Avila Beach, Ca

Post Reply

Who is online

Users browsing this forum: No registered users and 27 guests