1980 GS1000E Engine going "Clonk Clonk Clonk"

[terry]

G'Day Guys, well I just finished my 1980 GS1000E rebuild and it's looking good, however, when I returned from a ride today, I noticed a "Clonk Clonk Clonk" noise, that I'm sure it didn't have when I left my house a couple of hours earlier?

It's a typical GS1000 with maybe 50,000 miles on the odometer (the speedo and tach assembly was replaced by the PO after a crash, and the new odo only has a little over 10,000 on it, so I'm guessing) there is the usual cams "shuffling" noise, but this "clonk" noise seems to be coming from the alternator area?

It still starts easy and goes hard, will happily idle at 1000 RPM, and doesn't vibrate or anything. I dropped out the oil tonight after 100 or so miles after the initial start-up, (the bike hadn't been run for 5 years so I changed the oil and filter before I started it for the first time) and that oil, although a bit dirty, was metal-free, and there was nothing stuck on the drain plug magnet.

I replaced the horrible OEM auto cam chain adjuster with my own mechanical adjuster yesterday and that is working well, so it's not a cam chain issue. (I adjusted the cam chain with the cam cover off, so the chain is pretty much free of slack, but not tight)

I don't think it's the clutch, it doesn't make any difference noise wise if I pull the clutch in or leave it out, but it does seem to "gronch" when I go to take off in first. Once away the noise all but disappears, and today I saw 80-90 MPH with no problems at all, but at idle the noise is disconcerting.

Any suggestions? Thanks in advance guys! Cheers, Terry.

[wazz]

Broken starter clutch bolt ? Although they usually show themselves while starting.....

-greg

[Big T]

I hate to state the obvious, but your post covers just about every corner of the engine. If you can't figure out which cover the noise is behind, start pulling each cover until you find the problem.

[Suzuki mad]

Starter clutch in trouble.

Suzuki mad

[terry]

Hey thanks guys, I'll yank the starter clutch after work tonight! Cheers, Terry.

[terry]

Well you guys are great, I got home from work tonight and as it was still sunny and warm at 6pm here in Australia, (roll on summer..........) I changed into some shorts and a T shirt, and got amongst it. As I thought I might be in need of some spares, I attacked the starter clutch on a spare engine I had in the garage, only to discover that it was absolutely knackered, with all three bolts broken, badly damaged rollers etc. Oh dear..........

So it was with some trepidation that I removed the alternator cover on my bike. Sure enough, the starter clutch was moving independent of the rotor, but it looked like the bolts were still intact. After a good hour of coaxing the rotor off with all sorts of tools I finally had it off, and was able to unscrew the bolts by hand, without the impediment of tools.

Now I've never met the previous owner, (I bought it from a friend of his ex-wife, who was actually the registered owner, apparently he bought it for her, but she rarely rode it) but judging by his mechanical ability, I've decided that he's an idiot.

This guy had attached a sidecar to the bike's original frame by welding ugly home made brackets directly to the frame, and removing any OEM frame sections that got in the way, with an angle grinder. Even though it was a "one owner" bike, sadly the "one owner" was a moron.

So I shouldn't have been surprised to find that not only had he replaced the OEM rotor bolt with a standard Metric bolt with a few washers to make it fit, but the bolts he'd used to attach the starter clutch were cheap aftermarket "decorative" bolts, not quality high tensile bolts. Plus they were all loose..........

Anyway, apart from that the starter clutch was in remarkably good condition, so it was just a case of replacing the bolts with the correct ones, and re-installing everything. Once it was all together (around 9pm and getting dark) I fired it up, and was rewarded with a nice, quiet engine again. Excellent! Thanks again guys, I really was worried that it was a big end bearing! Cheers, Terry.