CX500 GL500 650 Global

Hello, I currently have a 1980 cx500c that needs a new cam chain. I am about ready to take it apart and do it as i've had great help from this site. Problem is, I have been reading my haynes manual. It talks about an old unmodified tensioner system and if its found, to replace it with the new modified system and plate and guide support plate. My question is, when I take off my bike's back motor cover, am I going to find the new tensioner design in there or the old one? I am trying to figure a ballpark cost before I do this job. Plus the guide blade, new style plate, and guide support plate are unavailable everywhere and I cannot find them. I am asking this because I am not sure I will have to convert my motorcycle to the new and better style. Any help is much appreciated

Thanks so much. I think I've pretty well got a list organized. Im going to replace the stator as well while i'm in there. Im also going to replace all coolant o-rings and thermostat (my guage would bounce around on a cold day). Thanks for the heads up on the mechanical seal on the water pump,I did miss that . It has 39,000 miles on it so I hope to be able to reuse all of the existing tensioner components and just replace the chain. I'm going to start the teardown this saturday and I'll let you know what I find

Hello again. I just took out the motor today. I have some bad and worse news... Someone has already been inside the rear and replaced the cam chain/tensioner system. The tensioner is nowhere near the end of adjustment limit. So I have no idea where the awful noise is coming from then. I put up a post about a year ago on the noise symptoms. And the worse news is that I broke off the rear end of the cam. I don't know what to do. I don't know whether to put in a used cam (if i can even find one) and just put it all back together or try to find another motor. It became unfomfortable to ride as the noise became louder and louder over time. The rattle noise it had only came when the engine was under load. But the oil has always been clean without any metal flakes plus this bike has been so very well taken care of. It looks like a brand new engine inside, no sludge or buildup anywhere. I don't see how it could be a bearing either. Some people have told me that they had a cx500 in the past and that it always sounded like a bucket of bolts. I really don't think thats correct. My bike sounded just like the sound file you posted on here of a cx500 idling with a bad cam chain. It had the same exact knock noise at idle There's so many questions now.. any help is appreciated as I'm very discouraged

I've been in your position.My 1st CX threw a shell in the 1st week I owned it.I had to decide whether to scrap it or replace the engine.I chose to replace the engine and the used the old one as a learning tool to get to know the engines.
In this instance I would try and source another running engine if possible or a cheap donor bike which is what I found which is now my main CX and my original is spare but good in the garage :/

No there never was any metal flakes of any kind in the oil. So i'm assuming that the bearings are fine. But to my question from previous, can a cam chain be worn out enough to make noise and grind against the casing even though its not stretched out enough to where the tensioner is at max adjustment?

Thanks so much for all of your help through all of this. If you wanna delete most of this posting that's fine with me. I just find it easiest to communicate with you this way. I have watched a few videos of cx motors with rod knocks that are so bad and loud, they make mine sound really good in comparison. So between that and the fact that I never found metal flakes in my oil, I am hoping i've caught it early and I will be able to only have to replace the rod bearings. And I would have known if there were metal shavings in the oil as I change the oil and filter every 2,000 miles faithfully.

Get the crank out and see what state the shells are in

Hello, got the big end shells out today. They are definately shot. Both have started to wear down to the copper in some places for the right piston. but the shells are intact and fairly thick, so i'm glad I caught them now. As for the crank journal, it has some very very light grooving (hardly noticable). Could I possibly get away with reusing the crank and replacing just the shells, or would that be a no no and just ruin the new bearings too soon? Also the majority of the cranks on ebay don't look any better than mine and some look worse than mine.

I've been here before.The 1st CX500 engine I did I didn't get checked and the crank looked good and I measured it with a digital vernier caliper.The engine only lasted around 12,000 miles before it threw the shells.It was then that I decided to do it properly and take it to a local engineering company(Yellow pages) that did re-bores and crank re-grinds.They checked the 2nd hand cranks I had AND the rods.They scrapped one of the cranks even though it looked good to me and my caliper saying it was below the service limits and had ovals.These could not be seen nor measured with our type of gear.
They also scrapped two of the 7 rods I gave them because of unseen stretch damage.Unfortunately it's very hard to get these cranks reground as Honda didn't make any undersized shells hence the use of decent 2nd hand cranks and rods in my case.
I took my Workshop manual with me to the engieering company and left that with them so they knew all the specs

You can do as you think but you have to ask,"Why did the shells go" in the 1st place and if their linings have gone then the crank will have worn as well

It can be better,if you keep your eyes out on Ebay,to get a set of rods with their crank off a low mileage example on Ebay?

However I would recommend professional crank and rod checking.

This crank looks absolutely beautiful and the price is just amazing.http://www.ebay.com/itm/221010442130?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649#ht_3645wt_1037 Tell me what you think of it . And my rods should be just fine as the bearings weren't let go very long so I was thinking of just matching the correct shell sizes for the stamps on this crank and using my rods. And the reason as to why the shells failed must be because a PO let the cam chain get really loose and the crank boss has a very large groove worn into it. So the there must have been metal flakes from that that damaged the big end shells. Someone got in there and replaced the chain and flushed the motor at a bear minimum and did not check the crank obviously