CX500 GL500 650 Global

Ok here is the story, I got this bike from a co-worker who is fairly well mechanically inclined. When he got it it would not start because it had been sitting for quite a while. He took it home and rebuilt the carbs, it fired right up. He worked on it a little over a few months doing routine tune up stuff, spark plugs, air filter, battery, new coolant, new oil and filter, and he even flushed out the brake system and put all new fluid in. He got it licensed and took it out for a ride. about 20 miles into his ride he was going about 45MPH when all of a sudden the oil light came on and 5 seconds later the back tire locked up. He pulled the clutch in immedialty and coasted to a stop. He waited about 15 minutes and hit the starter just to see if it would turn over, it did so he started it back up he was trying to get home see he drove slowly about another 1/2 mile and oil light came on again and it locked up again . He hauled it home in a trailer and at his house did the same thing...tried to fire it up and it started, but then froze soon after and it is now definitely STUCK. I drained the oil and looked for any metal flakes and I see very tiny silver particles but nothing big at all, oil looked brand new(it was only used for that 1 trip) It will not budge and I did some research to try and decide what could have e before digging into the motor, I am waiting for a manual in the mail. I thought maybe the oil pump quit working but I read those things are bullet proof and can last a long time, maybe the chain broke? He said it did not seem super hot like it over heated and the temp gage was just above center the whole time. What else could have caused this? This motor only had 20,000 miles on it and it was well taken care of, just sat in a garage all it's life. I did noticed when I drained the oil that he over filled it. Instead of being at the top of the hash marks on the dipstick it was up to the 4 fins closer to the top. That was with it sitting on the stand(not the kick stand, the one that pulls the back tire off the ground, Could too much oil in the motor cause it to seize? I can post pics up but someone will need to tell me how. I tried to put up a picture on my profile but have no idea what an avatar is. Anybody have any ideas about my situation? I plan to dig into the motor soon, but i am not sure where to start.

-Mike

Ok here is the story, I got this bike from a co-worker who is fairly well mechanically inclined. When he got it it would not start because it had been sitting for quite a while. He took it home and rebuilt the carbs, it fired right up. He worked on it a little over a few months doing routine tune up stuff, spark plugs, air filter, battery, new coolant, new oil and filter, and he even flushed out the brake system and put all new fluid in. He got it licensed and took it out for a ride. about 20 miles into his ride he was going about 45MPH when all of a sudden the oil light came on and 5 seconds later the back tire locked up. He pulled the clutch in immedialty and coasted to a stop. He waited about 15 minutes and hit the starter just to see if it would turn over, it did so he started it back up he was trying to get home see he drove slowly about another 1/2 mile and oil light came on again and it locked up again . He hauled it home in a trailer and at his house did the same thing...tried to fire it up and it started, but then froze soon after and it is now definitely STUCK. I drained the oil and looked for any metal flakes and I see very tiny silver particles but nothing big at all, oil looked brand new(it was only used for that 1 trip) It will not budge and I did some research to try and decide what could have e before digging into the motor, I am waiting for a manual in the mail. I thought maybe the oil pump quit working but I read those things are bullet proof and can last a long time, maybe the chain broke? He said it did not seem super hot like it over heated and the temp gage was just above center the whole time. What else could have caused this? This motor only had 20,000 miles on it and it was well taken care of, just sat in a garage all it's life. I did noticed when I drained the oil that he over filled it. Instead of being at the top of the hash marks on the dipstick it was up to the 4 fins closer to the top. That was with it sitting on the stand(not the kick stand, the one that pulls the back tire off the ground, Could too much oil in the motor cause it to seize? I can post pics up but someone will need to tell me how. I tried to put up a picture on my profile but have no idea what an avatar is. Anybody have any ideas about my situation? I plan to dig into the motor soon, but i am not sure where to start.

only my opinion.i wouldnt try starting the engine again,until youv investigated.take both plugs out,see if you can turn the engine over using the 17 mm nut under the rad.put a clean T shaped driver into each pot,seeing if it rises/falls with each piston.i think if this works you are in with half a chance.i dont think over filling would cause the engine it to sieze.id drain the oil and pull the front cover,get to the pump.suggest report findings.someone will give you help from there.

It does sound like an engine seizure.Only way to tell is to strip the engine

I did not try to start it at all, that was what he did to seize it in the first place. I tried the 17mm bolt under radiator, would not budge. What would have cause the oil light to come on right before it seized if it was full of oil? That is why I think it may be the oil pump. I will update this weekend, I plan on digging into it then. Hopefully I can figure out how to get pictures up for you guys...Thanks for the help!!

79cx500 wrote:I did not try to start it at all, that was what he did to seize it in the first place. I tried the 17mm bolt under radiator, would not budge. What would have cause the oil light to come on right before it seized if it was full of oil? That is why I think it may be the oil pump. I will update this weekend, I plan on digging into it then. Hopefully I can figure out how to get pictures up for you guys...Thanks for the help!!

Big end shell failure would cause the oil light to come on and the other symptoms.The bike should not have been re-started on the initial seizure.There would have been a possibility that the crank could have been saved if this is the case but usually it's destroyed as are the Con-rods which get stretched and why they must be checked by an engineering company if they are ever to be re-used.Failing to do this cost be an engine rebuild failure after 1500 miles.Lesson learnt in my case.
I know get the crank and rod/pistons checked prior to re-use or if sourced 2nd hand and machine polished on the crank and rod bearing faces.
Under normal circumstances you cannot get the crank re-ground as Honda did not make under-size crank shells.

Thanks for the info...if I need to order new internals, crank, rods, pistons, rings, etc. where is the best place to buy them? does anybody still sell them? I have found some companies outside the U.S. but would prefer to buy within the States if available. I am willing to put a some money into this if it is worth it. Should I just look for a new motor? I still plan on tearing it downa and will update soon. I figure it will be a learning exerience anyway!!

79cx500 wrote:Thanks for the info...if I need to order new internals, crank, rods, pistons, rings, etc. where is the best place to buy them? does anybody still sell them? I have found some companies outside the U.S. but would prefer to buy within the States if available. I am willing to put a some money into this if it is worth it. Should I just look for a new motor? I still plan on tearing it downa and will update soon. I figure it will be a learning exerience anyway!!

It's usually more cost effective to get another running engine but also watch out on Ebay for used ones.The one in my present engine came from the USA a couple of years ago off USA Ebay as the pound was strong against the dollar

There's some on there now,

http://shop.ebay.com/items/_W0QQ_nkwZcx500Q20crankQQ_armrsZ1QQ_fromZR40QQ_mdoZ

but don't forget to get the crank pins/rods checked even if they look good they may be stretched/warped if it is a bottom end lock-up.It's no bigger job to re-shell a 2nd hand crank and fit it than it is to do a Cam shaft change on these bikes so if you have a good basic tool kit and some knowledge it's not that bad a job.

Also

Copper flecks in the oil usually mean Big-end bearing failure.If you have caught it in time you can strip the engine and then get the crank and crank pins(Con rods) checked at a local engineering company that specializes in re-bores etc and also get the engine casing flushed/vapour blasted.I got them to machine polish the bearing faces of the rods and the crank after they had checked they were within service limits and of course the rods for stretch and burn.
Those parts are now in my Main CX and running well after around 2,000 miles plus.I also fitted new rings and decent cam chain and oil pump chain de-coked the heads,re-ground the valves and new valve stems seals,mech seal etc so it's pretty much a long term running engine now.
It does use a quite bit of oil but that's due to worn Valve guides which the cost of replacement to me with valves is too prohibitive(£300+/$600+) so I just use heavier cheap oil and keep an eye on the levels and an engine additive called Molyslip that cuts down on engine wear.

The good news is In all the CX engines I've stripped;built I've never yet seen the main bearings been damaged or worn enough for them to be replaced.This is most likely because main bearings have less chance of ,"Picking up a shell" as we say over here e.g getting F.O.D because of their position and also they don't have to suffer the extreme hammering that big -end shells get with the constant explosions from fuel ignition in the 4-stroke cycle.

ok, I am in the process of removing the motor and came acroos some questions, I almost have it out and need to know how to remove these 2 cables that go into the back of the transmission by the driveshaft. see picture below. It looks like its held on by that cover plate but I am not sure and cannot get it off because I cannot get to all the bolts! The one cable runs along the side of that cover and connects at the bottom of the transmission.



I have no idea how to get these off properly, any ideas??

Also, will the driveshaft slide out of the transmission as I back the motor away or do I need to remove the driveshaft another way?

If you haven't notice I am attempting to get the motor out without the manual as I am impatient and it has not arrived yet

Here is a better angle of the top cable...

You do not need to remove those cables to get the engine on a CDI Engine I think it's the same on a TI engine.You should be able to pull the small harness apart at it's connectors and feed the cables through the frame as you remove the engine.In fact it's best if you don;t remove the back plate at this stage.