Ciaran - GS500

Well I don’t have any pics just yet so you might have to wait a bit for some. The story goes a little like this.

I went to check it out a GS500 that I had seen advertised, the owner said it had a snapped cam chain. If the cam chain was broken it meant dropping the engine out of the bike and splitting the crank case, the price was right so I decided to take a chance. At first inspection it looked like the tensioner was cactus, with all the slack on the chain it was just skipping over the cam shaft sprockets making a god awful noise. Off I went down to the Suzuki shop and asked for a new tensioner. They had one in stock, I was so surprised, this kind of thing has never happened with the exception of sparkplugs and oil filters. In went the new tensioner and a repositioning of the crank shaft with the cam shafts had it looking like it just may work. Of course I was being extremely optimistic at this point, I put it all back together for test number 1. Pressed the starter and it turned over without any strange noises but didn’t start. A quick compression check with the old finger showed why and that something was still amiss with both cylinders, I couldn’t be arsed with taking it apart again so I left it for about a week.

With no compression it could mean only two things, air was going up past valves (bent or very dodgy valve clearances) or down (buggerd rings or holes in both pistons?). Even with a teaspoon of oil into the cylinders it still showed no gains in compression. I ruled out the rings. Once again I stripped down the bike. After a bit of light reading of the workshop manual, I discovered a line that states "You can remove the head without removing the engine from the frame." Well, last time I believe everything I read in a book. It is true that you can remove the head from the cylinders, you just can’t get it off the studs. I did however make a gap big enough to inspect the pistons, black but no holes.

This brings me to the point I am at now as I strip away all connections to the engine like drive chain, starter motor wires, clutch cable, exhaust and a few others in preparation for engine removal. I am so glad its air cooled.

I also checked the valve clearances on the intake side, spec says .03, left is .25 and right is .1 <!-- s:shock: --><img src="{SMILIES_PATH}/icon_eek.gif" alt=":shock:" title="Shocked" /><!-- s:shock: -->.

No doubt fun and games still lay ahead.

 

Sounds like your really launching into this one!
Would love to have the time and effort to pull apart a bike but i've been bitten very firmly by the 'must ride' bug... so not even time for a spray job until winter and 'other'* concerns kick into gear.

* = uni, financial woe, boredom, wet weather.

 

Did that belong to Lurch from OCAU? (originally from Nowra)

 

Sure did.

Nah my dad is cool with it, he has just as much crap all over the garage as I have, so his car probably wouldn’t fit if he tried. As for how the game is played, I don’t like to screw with things that work. Usually if it doesn’t work it is going to end up like you described anyway.

This is kinda the reason I got the bike. If I am going to get the FZR painted properly I will need some alternative transport. The GS was a good alternative to a working bike since I don’t need it on the road for a couple of months.

I am going to try and drop the engine out by the weekend, don’t hold me to that. So I will update this post with some photos then.

 

Had a bit of a play with the GS this arvo and removed the engine from the frame. It was a bit fiddly but with the help of a second person and a bit of tool improvisation it came out.

As I suspected the valves are bent. I took a picture of the head from the bottom up but it is hard to see the damage but I got a pic of the mark they left on the piston. The piston and conrods don’t look to be damaged apart from the mark in the photos. (The bit towards the bottom of the pic that isn’t black.)





I will be sending the head off to a shop to be reconditioned after I get my hands on some straight valves from Suzuki. I don’t have the tools or the expertise to do such a job so best to leave it to the experts.

Stay tuned.

 

What year is this bike and I don't think having a scored piston is bad for the bike Ciaran don't seem to any way.

 

The bike is an 89 model.

What you see in the picture above isn’t what you would call scoring. More of a dent. As long as it hasn’t weakened, cracked or changed the shape of the piston it isn’t a problem. Scoring when referred to a piston means something abrasive has become loose in the combustion chamber and scratched up the sides of the piston and the cylinder wall. That is bad.

After a bit of a clean up it is allot easier to see the damage to the valves, they should sit flush with the head and form an almost water tight seal unlike the ones in the picture.



I get the head back sometime late next week. Even after minor setbacks it is coming along nicely.

Only thing I haven’t decided yet is to get a new exhaust or not as the old one needs to be replaced. After scoping out the local wreakers it seems my options are to weld an old can onto the existing pipes or buying a nice stainless steel full system from f1. The new one is pricey but not out of the question and it looks and sounds great. The welding option is going to cost about a third of the new system but is rather bland. Either way the carburetors need to be re jetted and that has already been factored in.

Since I am probably going to sell the bike after a few months what do you guys think?

 

I checked out 'the dull one' this arvo and it seems in fairly bad shape. The can itself is dented a little and a rather noticeable scrape down the side. I have got onto findapart to look for one in a bit better nick, we'll see what it will turn up. If I was going to use the one at the wreaker it looks like its going to need welding, painting, the old sheet metal cover cut off and a new one welded on and it is still going to have visible dents in it. That’s about 2 weeks of waiting around if I don’t do the welding myself but I would probably stuff it up. <!-- s:lol: --><img src="{SMILIES_PATH}/icon_lol.gif" alt=":lol:" title="Laughing" /><!-- s:lol: -->

If I can’t get a decent one off findapart I will give my mate a call and see if he would be willing to spring for the extra hundred or so for the quality pipe.

 

Update : 15 March

A week late but nothing has really happening to post about. The head is at the shop still with everything needed except the head gasket. I am waiting for it to arrive on a slow boat from Japan next week. After looking deeper into costs for second hand exhausts I ended up going for the f1 system. Headers where out of stock so they should arrive next week or the week after. I have done a fair bit of cleaning stuff up and little bits of painting but I can’t wait to get the bike back in one piece.

 

Hey not wanting to sound like to much more like the noob I am (but this project sounds interesting) - could you post some pics of your bike and what it is supposed to look like?

 

I’ve been putting off posting up pictures of the bike but I guess I could wheel it out into the daylight and take a few happy snaps on Saturday arvo once I recover from St Patrick’s day celebrations.

I don’t have any pictures of the bike together. I did find this picture though. If it looks even close to what this bike does I will be happy as Larry.

Well it is only going to go as far as a new air filter exhaust and rejetting to suit. From what I have gathered from talking to a few people that have gone before, it should get the power up by 5~10% but I wont believe that till I see the numbers on paper.

I want to hang onto if for a few months before sale though I will make more long term plans once it is running. I want a bit of time to enjoy the bike before I find it a new home.

 

I swear the first time I saw the colour was the day I went to pick it up. <!-- s:roll: --><img src="{SMILIES_PATH}/icon_roll.gif" alt=":roll:" title="Rolling LoL" /><!-- s:roll: -->

I'd be lying if I said the track bike thought hadn’t crossed my mind but how would the GS cope with weekend duties up into the mountains?

 

Quite well.

 

Ok I have a few new pictures of the bike.

This is what I have managed to do to the bike up until this morning. Apart from pulling it to bits and scattering the parts in a random fashion, I gave it a clean up and painted the center stand after removing a bit of rust.


I picked up the head and various gaskets and o rings from Bruce’s on Friday after work and set about putting it all back together today after buying some oil. At the bike shop I noticed a nice clean TRX850 out front for 5k mmmmm.....

Here are the new valves freshly seated in the head.


After four weeks sitting on the bench taking up space it was time to get back to work. Note the size difference with the giant piston off a centurion tank!


Almost together. It took some time getting the camshafts lined up correctly with the slack in the chain at the right places because the camshafts would move when you tightened the bearing caps.


And finally after about hour of wrestling prying and levering I managed to jam the engine half way in and out of the frame. <!-- s --><img src="{SMILIES_PATH}/icon_mad.gif" alt="" title="Mad" /><!-- s --> We managed to get it out and take off the cam cover and the alternator cover for attempt number two. With the covers off it went in after only 15 more minutes of positioning. Boy am I glad that’s all over.

Put the covers back on and decided to call it a day and rest my bloodied knuckles.



Unfortunately when the alternator cover came off the gasket broke so the bike won’t be running this weekend. If it takes another 3 weeks to come from Japan I may just kill somebody down at the parts counter. Not to worry the exhaust it due to arrive during the week sometime but I will check on Monday. It also gives me time tomorrow to epoxy the inside of the tank. One question though, If I epoxy the tank now will that foil any attempts to remove dents in the future???

PS. I have started using imageshack.us rather than photobucket as when I went to upload new pictures they shrunk to 320x240?