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Main Area => Odds n Ends => Topic started by: dread_au on September 28, 2010, 04:27:28 PM

Title: Questions about engines
Post by: dread_au on September 28, 2010, 04:27:28 PM
Ok I have has a gs500 for 2 years now and done all the work on it myself. I am not afraid to try the mechanical stuff.

I have just started on a project bike (a suzuki gsx250f 93). There is not a real lot of info on the net about this so I hope you guys don't mind me asking questions here.

The engine is in pieces when I picked it up. Looking at the carb settings I think this may have been the problem but won't know till its all back together. Is there anything I should be looking for? It is a 16 valve 4 cylinder water cooled. (Sorry in advance if I get the terminology wrong) Everything that the pistons and above has been taken off and the 2 side covers.

should I re-hone the cylinder sleeves? Will I need oversized pistons( I have found 0.5 mm oversized ones)
what type of epoxy should I use on the magnets to stop the goats?(the epoxy has come away in one spot)
Which gaskets have to be glued down?
Do I need to locktite bolts in the engine or use special glue?

Thanks for reading and any suggestions would be good. I will put up pics soon on my progress
Title: Re: Questions about engines
Post by: Big Rich on September 28, 2010, 07:29:16 PM
Have you found s service manual yet? Well, you should measure the diameters of the pistons and cylinders to see what needs done. The cylinders should be honed while you're in there. If they need bored out, bigger rings should be all that's needed, not bigger pistons.
Title: Re: Questions about engines
Post by: dread_au on September 29, 2010, 03:36:17 AM
Yep got a manual. Well the only one I can find and diagrams of the exploded parts as well. Thanks big Rich I will have a look at the diameter sizes. Should I just change the rings as a precaution since it should be relatively easy in its current state? :dunno_black:
Title: Re: Questions about engines
Post by: Big Rich on September 29, 2010, 03:40:25 AM
Couldnt hurt. But if you're not afraid to get back in the motor - that's your call.
Title: Re: Questions about engines
Post by: bill14224 on October 01, 2010, 08:58:17 AM
If the cylinders measure in spec and are not scored you can throw new rings in it and put it back together, that is as long as you're convinced the crank, bearings, and heads are in good shape.  Examine the whole thing and go from there.  How many miles on the engine?  Not enough clues for us here yet.
Title: Re: Questions about engines
Post by: dread_au on October 05, 2010, 02:23:58 PM
51 000 kms on the engine according to the speedo. I will try to get some pics on today.  Thanks for the help so far
Title: Re: Questions about engines
Post by: JAY W on October 05, 2010, 03:14:13 PM
Quote from: Big Rich on September 28, 2010, 07:29:16 PM
Have you found s service manual yet? Well, you should measure the diameters of the pistons and cylinders to see what needs done. The cylinders should be honed while you're in there. If they need bored out, bigger rings should be all that's needed, not bigger pistons.
No such thing as oversize rings,rings match the piston,oversize piston and rings if neccs`.
edited,sorry Rich,In my time as a bike mechanic never came across ov` rings,learnt something today.(maybe i could get some for my blackbomber 450)
Title: Re: Questions about engines
Post by: Big Rich on October 06, 2010, 05:47:18 AM
I beg to differ. I have a 68 Honda that was bored out .25mm over - original pistons & .25 OS rings. The inner diameter of the pistons rings is the same, the outer diameter is only .25mm larger.

I dont know about the GS500 (never looked), but they make oversize rings for every older bike i work on.
Title: Re: Questions about engines
Post by: The Buddha on October 06, 2010, 11:24:19 AM
They (the car engine guys I know that also do some bike motor work) say that .25 is the largest you can bore and just cover it with rings.
However to shaft the person that is thinking of doing that, suzuki sells the rings only with pistons. Of course they sell standard rings all by themselves ... just not the .25 or .5 over.
I'd get total seal or some other rings if you doing just rings on an overbore.
Cool.
Buddha.