750 Engine differences

[OldBike]

I've been reading here and got a question about these bike motors on the 750's... I noticed the service manuals on ebay seem to go to 1982... Aren't the TSCC motors for the 750's all the same? If not whats the difference?

http://cgi.ebay.com/ebaymotors/SUZUKI-GS750-ELT-GS750E-GS750L-GS750T-MANUAL-1977-1982_W0QQitemZ8017756257QQcategoryZ38663QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[robinjo]

From '83 on there was a new generation of 750's (700) , just one step away from the GSX-R.

[focus frenzy]

there are three generations of GS750 engines
76-79 first gen. two valve (actualy weighs more than first gen 1000 engine!!)
80-82 second gen. four valve tscc engine,electronic ignition, still big and heavy.

83-85 third gen. four valve alot of weight has been shaved off and differant design from previous generations.

the GS1000 only had two generations but three versions.

gen 1 two valve

gen 1.5 two valve but larger stronger clutch basket, bigger intake ports for CV carbs electronic ignition. also a shaft drive version of gen 1.5

second generation is rare 16 valve version of 1100 engine, only used in first year Katanas

the GS twins get complex
first generation, 77,78 and possibly early 79,two valve 400cc roller crank

gen 1.2 1979 2 valve 425cc roller crank

gen.1.5 1980-85 2 valve 450cc roller crank

gen 1.7 1989- present 2 valve 500cc roller crank, the cylinders and head have more fins but on the inside is is just a 3mm over bored 450

generation 2 1980-85 4 valve 400 sold outside the US plain bearing crank, actualy makes 1hp more than 450, 250/300 baby twin is based on the 2nd gen.

[cloudbreakmd]

Hmmm... This is an interesting thread...

What manual (and where do I find it) would I use for my 1983 GS750T TSCC 16-valve?

[JayH]

there are three generations of GS750 engines
76-79 first gen. two valve (actualy weighs more than first gen 1000 engine!!)
SNIP

The 76-9 are pretty easy to identify - look for a kickstarter on the right side of engine. If the bike is still stock it will still have points.

[moto_dan]

Hmmm... This is an interesting thread...

What manual (and where do I find it) would I use for my 1983 GS750T TSCC 16-valve?

The '83 750 T used the 2nd generation engine, 1st TSCC engine. You may be able to find an manual for the '83 "T" model, but for engine work a manual for an '80-82 GS750 should suffice. Good luck.

[robinjo]

Leon do the 550's follow the 750 with the technical progress?

[focus frenzy]

Hmmm... This is an interesting thread...

What manual (and where do I find it) would I use for my 1983 GS750T TSCC 16-valve?

The '83 750 T used the 2nd generation engine, 1st TSCC engine. You may be able to find an manual for the '83 "T" model, but for engine work a manual for an '80-82 GS750 should suffice. Good luck.

Sorry Dan, you might want to take a closer look at your 83, its engine is totaly differant from the engine used on Tims 80or 81 750.

[focus frenzy]

Leon do the 550's follow the 750 with the technical progress?

the 550 was passed right over in 1980 and didn't get 16 valves till a total redesign for 1983

1977-79 first gen, two valves, old school slide carbs, points ignition kick start

1980-82 gen 1.5, updates with bigger intake ports and CV carbs, electronic ignition, kick start deleted.

1983-85 gen.2, clean sheet redesign that resembles the 3rd gen 750 but is not interchangable due to unusual intake port spacing and carbs used on the 550 to clear the frame down tubes that come down close to back of engine.

[cloudbreakmd]

Sorry Dan, you might want to take a closer look at your 83, its engine is totaly differant from the engine used on Tims 80or 81 750.

If I am understanding this correctly... I have the third generation GS motor? Would that be the reason the manual only lists up to 1982? Although looking at the side of the bike posted above, my clutch case is shaped different (not recessed as above).

[ResidentWarui]

Leon do the 550's follow the 750 with the technical progress?

the 550 was passed right over in 1980 and didn't get 16 valves till a total redesign for 1983

1977-79 first gen, two valves, old school slide carbs, points ignition kick start

Interesting because my bike has kick start and electric 8O

I guess someone put in the electric start when they did the ignition...

It's nice to have the kick start though because I could never get it started with those horrible carbs on there without draining the battery

-Simon

[focus frenzy]

Sorry Dan, you might want to take a closer look at your 83, its engine is totally different from the engine used on Tims 80or 81 750.

If I am understanding this correctly... I have the third generation GS motor? Would that be the reason the manual only lists up to 1982? Although looking at the side of the bike posted above, my clutch case is shaped different (not recessed as above).

OOOOOOOOOO my bad, Sorry Dan, I didn't pay attention to the T part.

the 82/83 750T is a economy model and uses left over 2nd generation engines, after further digging, the 83 750S katana also uses the second generation engine. the katana got the 3rd gen engine in 85.

the third generation 750 engine makes 5 more HP and weighs less than the second generation engine.
a obscure bit of info::: suzuki did build a water cooled GS, the GSX400FW
is was a 400cc four cylinder 16 valve engine that made 58hp, they also made a four cylinder GS500 (air cooled), both only sold in Europe.

Simon , all GS (with possible exception of the GS125) have electric start. bikes made before 1980 (Kawasaki's also!!) had a back up kick starter.

back in the good old days all bikes had kick starters even bikes with electric starters also, when electric starters came out, they were not the most reliable thing, especially with 6 volt electrical systems.
in the late 60's 12 volt electrical systems started to displace the 6 volt systems and battery quality improved, in the late 70's batteries were powerful enough and starters were strong enough that kick starters were no longer needed.

[robinjo]

Sorry Dan, you might want to take a closer look at your 83, its engine is totally different from the engine used on Tims 80 or 81 750.

If I am understanding this correctly... I have the third generation GS motor? Would that be the reason the manual only lists up to 1982? Although looking at the side of the bike posted above, my clutch case is shaped different (not recessed as above).

OOOOOOOOOO my bad, Sorry Dan, I didn't pay attention to the T part.

the 82/83 750T is a economy model and uses left over 2nd generation engines, after further digging, the 83 750S katana also uses the second generation engine. the katana got the 3rd gen engine in 85.

the third generation 750 engine makes 5 more HP and weighs less than the second generation engine.
a obscure bit of info::: suzuki did build a water cooled GS, the GSX400FW
is was a 400cc four cylinder 16 valve engine that made 58hp, they also made a four cylinder GS500 (air cooled), both only sold in Europe.

Simon , all GS (with possible exception of the GS125) have electric start. bikes made before 1980 (Kawasaki's also!!) had a back up kick starter.

back in the good old days all bikes had kick starters even bikes with electric starters also, when electric starters came out, they were not the most reliable thing, especially with 6 volt electrical systems.
in the late 60's 12 volt electrical systems started to displace the 6 volt systems and battery quality improved, in the late 70's batteries were powerful enough and starters were strong enough that kick starters were no longer needed.

Dan beat me too it. Second generation motor was indeed used on some models after '82, I also know of some old style 1100's around here upto and including '87 but could be registered a few years after manufactured date...

Also 550 wasn't available untill 1978 not '77, just the 750 and 400.

I also was surprised when I opened up a '81 550 (Bob ) to find there was still the possibility to install a kickstarter in the crankcase, atleast the hole where the kicker shaft goes, seems they only modified the cover.



All is well with Bob, just a bit leaky gasket, fixed and now a nicely painted clutch cover.

[cloudbreakmd]

I thought the L model was the economy model? But thanks for answering my question. So I should just get the GS750 manual up to 1982 right?

[ResidentWarui]

Simon , all GS (with possible exception of the GS125) have electric start. bikes made before 1980 (Kawasaki's also!!) had a back up kick starter.

back in the good old days all bikes had kick starters even bikes with electric starters also, when electric starters came out, they were not the most reliable thing, especially with 6 volt electrical systems.
in the late 60's 12 volt electrical systems started to displace the 6 volt systems and battery quality improved, in the late 70's batteries were powerful enough and starters were strong enough that kick starters were no longer needed.

ic, thanks for clarifying 8)