Overheat, now engine scrape, pic included

[Bustedknuckles]

alrighty, so i have been rebuilding this 82 gs1100 for the past few months and finally got it to running condition (i thought) because of the mods i have done to it it was running lean and overheating. i didnt know this would happen and didnt recognize it until after about 30 min of riding. :-#

once i realized i was overheating the darn thing i parked it, let it cool off and then rode it home. once home i changed the oil, put new plugs in. and ordered and installed a dynojet kit. now the bike is really hard to even get started, i have to mess around with the idle screw and choke for such a long time that i end up killing the battery before it even starts.

When i finally do get it started it makes a knocking noise coming from i believe the cylinder housing. and when i take it down the street it makes a horrible scraping sound that matches my speed at all times, (the faster i go the faster the scraping) and i believe the scraping is coming from the crankcase.

needless to say im not riding it anymore or even starting it until i get these two problems sorted out. the bike doesnt overheat anymore. its just REALlY hard to get started and when it does start the engine knocks and the crankcase scrapes when in motion.

----What are some common mechanical failures due to overheating in this part of the engine that could cause this?

----below is an image of where the scraping is occurring. again it matches whatever speed im at.

 

[Bustedknuckles]

where knocking is

where knocking is

and here is an image of where the engine knock is coming from. im guessing its a piston rod or something but i really have no experience with these bikes other than rebuilding the carbs and riding them. any knowledge on what it might be would be greatly appreciated.

 

[TheCafeKid]

The cranks on those 8v motors are tough. 16v 1100 too but that's not what you have, so... That noise, and the subsequent hard to start are likely the starter clutch, and a need for the proper jetting and a valve adjustment.
Starter clutches on the big displacement 8v motors were pretty prone to needing replacement every 20 years or so it happens.

Behind that cover (the double round one) is your charging rotor/starter clutch assembly. In the cover is the charging stator. You'll have to get the charging rotor off to replace the starter clutch, which you'll need a puller to do. Be careful, the rotor is somewhat fragile as it's made up of magnets that will shatter if you smack it with a hammer in anger because it won't come off.

Do a search on starter clutch replacement, I'm positive there are quite a few threads on the subject

 

[Bustedknuckles]

sweet, thanks alot cafekid,

as long as i dont have to pull the engine out im okay with it. so your saying the scraping is the starter clutch? i can def. do that, any advice on the knocking?

 

[TheCafeKid]

Both sounds may be the symptom of the starter clutch being bad.
It's hard to explain without pics or without being familiar on how it's put together, but the starter clutch is a sprague clutch. It uses a few roller to lock onto the crank as the flywheel it's attached to is spun by the starter. When the crank speed becomes faster than the starter speed, the rollers let go.
The starter clutch is held to the flywheel and charging rotor with some largish bolts, but over the years the repeated inital shock of the torque against the compression stroke cause the clutch to kick back against the gear and eventually the bolts get loose, shear off, or the thin sheet metal housing holding the rollers and springs inside the clutch assembly fails. This causes, usually, a bunch of racket down there. And it's hard to pinpoint the location of origin, but if it's making a shuffling, knocking noise, from the left side of the motor, the starter clutch is a good place to start.