Author Topic: rod bearing gone bad (Read 3649 times)

spence27 · « **on:** January 04, 2007, 06:51:23 PM »

I have a 2001 1200 with a deteriorated big end rod bearing. The bearing does not seem to have moved, just went away and off to the sides between the crank throws.Some bearing still sits in place on the rod. Crank has lots of marks on it but not sure at this time if there is any depth to them or if they are actually on the surface. Has anyone had an experience like this and what is recommended course of action to repair as inexpensive as possible but also with long term reliability? Thanks.

CWO4GUNNER · « **Reply #1 on:** January 04, 2007, 11:02:10 PM »

From my experience with other air cooled engines. Anything short of a complete disassembly, inspection and measurements and line bore is a big gamble. Although I have heard of lucky people who have replaced the rod and bearing and moved on without problems. But if your going to go that far, you might as well disassemble it and take it to a good Japanese motorcycle machine shop to assess the true damage. At least after that you can reassemble a new engine.

Bob Holland · « **Reply #2 on:** January 05, 2007, 09:59:01 AM »

I have had a lot of experience with this, I replaced the crank on my Bandit once and three times on my GSXR 1100, and a half dozen or so on ZX 12s and Busas for other people. When one bearing goes, the medal from it usually gets the crank bearing on that journal and the one next to it. The cranks can not be turned down, but they can be polished, if the scores or not to deep. The journal can be welded and turned, but the cost for two journals is more than a new crank. If you have to have a new crank, you will need to get the new crank in hand and then caculate which bearings you will need, to order the bearings. Either way, you will need to disassemble your engine, your oil pump and trans to clean out all bearing particals, so as not to damage the new bearings.
Every time I have changed a crank, I had to replaced 1 or 2 rods, which means the head has to come off. The last time I checked, the dealers charge around $2000 for this plus parts, so if you can't do the work yourself, you may want to look for a used engine.

CWO4GUNNER · « **Reply #3 on:** January 05, 2007, 12:48:03 PM »

BHolland sound like the man in the know. One other thing he mentioned that cant be overstated about removing all the bearing particles which like cancer will spread to whatever new parts you install if not completely cleaned and flushed out. Example I blew a completely good used engine just 20 minutes into operation because I sued the old oil cooler radiator from the blown engine without flushing it out. The hardened bearing particles lust spread like cancer and took out the bearings on the good used engine. I was about 22 at the time and cried because I had spend so much time cleaning and preping only to forget the dam oil cooler.

spence27 · « **Reply #4 on:** January 05, 2007, 08:22:48 PM »

Seems to me the best thing I can do is find a good used engine and go with that. I would like to do that if I can find one at a fair price. Anyone who knows where I might be able to get a low mileage engine at a good price I would appreciate hearing from. Thanks

CWO4GUNNER · « **Reply #5 on:** January 06, 2007, 12:28:31 AM »

Occasionally I look in Cycle Trader on line for deals and I am always seeing B12 for good prices especially ones advertised by salvage yards with fork and fairing damage. Its a sad thing when an engine blows. Your story makes me want to change my oil and stay off the rev limiter.