"L" shaped timing tensioner

[Andy.tech]

Hi, I purchased my 1990 gs500 used and it has an "L" kinda shaped timing chain tensioner. Is this normal?

[Big Rich]

Can you take a picture of it?

I want to say it is a CCT from a GS450 that was rigged to fit your 500. Can't imagine why since both models have the same failure rate (next to nothing). But the 500's plunger is a larger diameter than the 450, so you can't use a 500 plunger on an older bike (but vice versa is fine).

[Andy.tech]

Do you think this cylinder is from a GS450? And if it is, should I change it or can I leave this part here.

[Watcher]

Can you take a picture of it?

[Big Rich]

"If" the cylinders are from a 450, they should have the cc's cast into the front. Again, I don't know why anybody would put smaller cylinders on any bike but it is possible. Most likely it's just the CCT that was swapped.

[Andy.tech]

[The Buddha]

Oh yea different cyls.
I think the 450's tensioner will fit the 500 but that isn't a 500's cyl and it isn't the 450's head WTF was done to that bike ? pic of the whole bike would throw some light on the guy's mentality.
Cool.
Buddha.

[Big Rich]

Ha.....most likely, I was wrong. Somebody did put 450 cylinders on a 500 engine.

Well Andy, the good news is that if the engine keeps running you're golden. Just missing out on 50 cc's. I'm wondering if the P.O. had a GS450 that they wanted to "hot rod" and your GS500 was the donor bike? If that's the case, they may have slapped the engine together to get it running and sell it.

[Andy.tech]

I changed the tank and put the 89 clipon's and the Katana rear wheel along with the rear plastics. Been trying to get her to look and run nice I also did the exhaust

[The Buddha]

Ha.....most likely, I was wrong. Somebody did put 450 cylinders on a 500 engine.

Well Andy, the good news is that if the engine keeps running you're golden. Just missing out on 50 cc's. I'm wondering if the P.O. had a GS450 that they wanted to "hot rod" and your GS500 was the donor bike? If that's the case, they may have slapped the engine together to get it running and sell it.

Naaa they prolly cut the bore 2mm is it or 3 ? So it could run the stock GS pistons and the stock GS carbs.
Cos it probably would have been a beeeeyotch to get a GS carb rack working with a 450's swept volume, cos 1mm over on a GS stock bore will need different pilots and mains ... so unlikely they managed to get it to work at all 2-3mm under.

Its a lot cheaper to get a scored up 450 cyl and clean it up to the worn GS piston than it is to get a clean 450 cyl and piston set and that doesn't even consider the carbs. In my neck of the woods (literally) GS450's lying face down in the mud in the junkyards are a dime a dozen.

Cool.
Buddha.

[Andy.tech]

Yea it had the GS pistons in it, but is it ok for it to stay or should I be looking for a GS cylinder? At the moment it's running I was just experimenting today with different jets. I'm at 5000 feet at the moment and I' tried the 37.5 pilot wit 140 main but I don't think it's working, can't get it to idle so I'm thinking of going with a 42 pilot and leaving the 140 main since at 5000 feet there is less air.

[The Buddha]

37.5 is too lean 42.5 is really not a pilot I've ever used. Maybe with a 2mm overbore.
Cool.
Buddha.

[Andy.tech]

Yea I was thinking 37.5 because it came with the carb and I'm at 5000 feet

[The Buddha]

High Altitude probably needs the stock jetting.
You're running 140's with what filter and pipe ? K&N and stock pipe ? oh you have a slip on - no, you're definitely going to need more than 140. Maybe not the 150 of K&N and pipe but maybe 147.5.
You may be fine leaving the needle without a shim, and pilot as is, but go to 150 mains.
BTW stock needles or DJ ? DJ has adjustable grooves on top for the e-clip.
Thanks.
Srinath.

[Andy.tech]

When I took it apart I didnt have to put the shims cause I was able to move a "c" clip type thing for the needles
. I dunno if thats DJ. My yes I have a lunch box filter and free flow slip on exhust

[The Buddha]

When I took it apart I didnt have to put the shims cause I was able to move a "c" clip type thing for the needles
. I dunno if thats DJ. My yes I have a lunch box filter and free flow slip on exhust

OK DJ - if your top end is fine leave it alone, cant rejet with that needle.

If you're rich with 37.5 needles maybe try a 35 - I also think you could have high floats. Check and adjust too.
Cool.
Buddha.

[Andy.tech]

Thank you, i just ended up using the 42 pilot and 140 main and it seems to be working well but I am concerned with this 450 cylinder. At the moment i do not notice anything wrong but is it ok for it to stay?