GS750EX 81 to 83 GS750ES Engine

[922toms]

Has anyone took a 1981 GS750EX engine and installed it in a 83 GS750ES Frame? Thanks Tom Would it fit with modifications? Thanks Tom

[blowerbike]

not even close to a bolt in.
a GSXR engine would be better suited.

[Nessism]

That would be a downgrade. The 2nd gen 750 engine is the only one that isn't bullet proof, plus it's heavier than gen 3.

[922toms]

81 gs750ex engine to 83 gs750es frame

Would this fit? Thanks Tom

[922toms]

Hi, Will it WORK WITH A FEW MODS? Thanks Tom

[rapidray]

Tom, ANYTHING can be MADE to work! Which part of the above posts are you not getting?! NOT a good motor to use! Ray.

[xjandgs]

There is nothing wrong with that engine

There is nothing wrong with a GS750EX engine... I have essentially the same engine which had some subtle changes made by Suzuki for 1982 - the GS 750EZ. DOHC 16 valve... Everything I have read suggests that they are just as bulletproof as the highly regarded 1st generation 8 Valve GS engine - as well as powerfull and strong. The performance numbers are not that far off from the E and ES bikes of 83-85. I believe quarter mile on 81 was around 12.5; my 82 - 12.0 and the 83 engines ran their bikes at just under 12.0 (horsepower and torque - as well as flexibility pretty much the same between all 3)

Might it be he has access to the engine he is asking about at a good price and does not mind it being a couple of years (older) that what was originally in his bike...

Geez - why do people here have to impose their opinion ... Everyone has one but there is a time and place to share it. So this will be my time to share it...

If it is a bolt on fit - go for it... that is a sweet engine.

[BassCliff]

Greetings and Salutations!!

Hi Mr. 922toms,

You don't know me from Adam, but I would trust the opinions of Mr. Nessism and Mr. rapidray. I know these guys personally and they have been working on the GS line of bikes for decades. Sure, the second generation engines had some oiling issues but if you're diligent with your maintenance it should not be much of an issue. Right?

Let me just offer you some documentation, dump a TON of information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. This is what NOT to do: Top 10 Newbie Mistakes. Now let me roll out the welcome mat for you...



Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[Nessism]

Yes, oiling issues. There have been a number of GSR members here that have wasted cranks and heads/cams/rockers because the oiling system is deficient. My understanding is that Suzuki promoted a fix back in the day where the oil pressure relief spring is shimmed by .060" to increase oil pressure. The oiling issues aren't bad enough to regulate the 2nd gen. 750's to the do-not-purchase list, but I wouldn't go though all the hassle of shoehorning one of those beasties into a 3rd gen chassis either.

[xjandgs]

GS 750ET, EX, and EZ

My 1982 GS 750 has over 40,000 miles on it and by all accounts (that I have been privied to) it is still a baby. My understanding is that the oiling issues noted below only come into play for those who tend to be somewhat negligible in oil and oil filter changes.

I just bought a GS 850 and love this bike in the short time I have had it, but quite frankly the bite and performance of my 750E (with this 2nd generation engine) is truly head and shoulders more exhilirating.

Like many - the ones who have problems are the ones who voice opinions b/c they are the ones venting and needing "fixes." How many other 2nd Generation engines out there have gone on for many miles hassle free. Those generally are the ones you don't hear about b/c there is no reason to vent or asking for help. So from one who has had no problems and one who knows no one having problems - I say it is arguably one of the best UJM engines out there.

LOL ---- I never thought I would be having to defend 1980's GS engines - let alone on this site ... and I don't know either of the gentleman who gave their earlier opinions, knowledgeable or not to put down that engine (especially in the manner) and with the added sarcasm to an honest question by the one guy who asked "which part of the above posts are you not getting?! NOT a good motor to use!" is laughable....

[rapidray]

After being a Suzuki dealer mechanic DURING the early to late 80s I speak from EXPERIENCE about the 2nd gen 750 motors. They are not only a poor design in the oiling department but a poor choice for a transplant into ANY bike when there are much BETTER engines available! Again, this is EXPERIENCE speaking not opinion. Ray.

[Nessism]

My 1982 GS 750 has over 40,000 miles on it and by all accounts (that I have been privied to) it is still a baby. My understanding is that the oiling issues noted below only come into play for those who tend to be somewhat negligible in oil and oil filter changes.

I just bought a GS 850 and love this bike in the short time I have had it, but quite frankly the bite and performance of my 750E (with this 2nd generation engine) is truly head and shoulders more exhilirating.

.

There have been several long term GSR members here that have suffered oil related failures on their 2nd gen 750 engines. These are NOT isolated incidents by thrashers. I strongly advise you to shim your oil pressure relief spring ASAP just to be safe. I also suggest use of a high quality synthetic oil, either diesel engine or motorcycle oil. I wouldn't use automotive grade oil in any GS, but particularly so in the 2nd gen 750.

[haztoys]

After being a Suzuki dealer mechanic DURING the early to late 80s I speak from EXPERIENCE about the 2nd gen 750 motors. They are not only a poor design in the piling department but a poor choice for a transplant into ANY bike when there are much BETTER engines available! Again, this is EXPERIENCE speaking not opinion. Ray.

And I will back Ray on this ...I have the same back ground as Ray ...Suzuki dealer mechanic in the 80s.. A short stint with Suzuki RnD ... And where Ray has ended up in the drag racing world ...I end up in the road-racing world ...My experience with the 2nd gen gs 750 motor is the same as Rays ....

Just because you find a motor and its on hand ..Does not make it a good swap ...

[xjandgs]

There have been several long term GSR members here that have suffered oil related failures on their 2nd gen 750 engines. These are NOT isolated incidents by thrashers. I strongly advise you to shim your oil pressure relief spring ASAP just to be safe. I also suggest use of a high quality synthetic oil, either diesel engine or motorcycle oil. I wouldn't use automotive grade oil in any GS, but particularly so in the 2nd gen 750.

I am sure you do but would you also say you know SEVERAL who did not have any problems. That is the point I am making. Again, I never thought I would be defending a GS engine on this site...

Any way just exercising my voice here (it is just a counter view to the negative ones given below) - simply put.

10W 40 traditional oil works for me (and of course MOTORCYCLE OIL) - the automobile oil does not have the additives to entertain the fact that it is a wet clutch with the transmissing and the engine sharing oil from the wet sump for this engine... could not imagine using automotive oil, could you? Synthetic is fine for those who tend to lean away from regular maintenance - and all the power to those who use it - but I have never had the need for synthetic oil and should for any reason I have the problems you suggest, I am sure using synthetic instead of non synthetic oil won't remedy the problem.

All of the above being noted and what has been noted below --- I am done discussing this. Thanks.

[Nessism]

I am sure you do but would you also say you know SEVERAL who did not have any problems. That is the point I am making. Again, I never thought I would be defending a GS engine on this site...

Any way just exercising my voice here (it is just a counter view to the negative ones given below) - simply put.

10W 40 traditional oil works for me (and of course MOTORCYCLE OIL) - the automobile oil does not have the additives to entertain the fact that it is a wet clutch with the transmissing and the engine sharing oil from the wet sump for this engine... could not imagine using automotive oil, could you? Synthetic is fine for those who tend to lean away from regular maintenance - and all the power to those who use it - but I have never had the need for synthetic oil and should for any reason I have the problems you suggest, I am sure using synthetic instead of non synthetic oil won't remedy the problem.

All of the above being noted and what has been noted below --- I am done discussing this. Thanks.

You might want to do some research on oil. Synthetic oil holds up to high temperatures much better than dino oil; it maintains it's film strength and doesn't flash off as readily at high temps. Given that our bikes are air cooled and the oil temperature will routinely crest 320+F during summer riding, and your engine has a weak oiling system which means only a minimum amount of oil may get to the top end during the heat of summer, using synthetic oil may very well save those camshafts and rocker arms, if you were to choose to use it that is. Do what you want but implying synthetic oil only useful to those that abuse their engines shows how uninformed you are.