81 kz750 E2 or L1

[hipstir70]

I have a frame I'm trying to work out for a long term project I have. Am I correct in that it's a kz750 L1? Were both bikes E & L available here in 81 as they have only very minor differences. Which one was classed as the sporter bike out of the two as opposed to the H.
With my 1980 E1 I didn't have to worry it as there was only H1 to worry about in the 4 cylinder.
I'm about to start collecting some parts as I want to bring back to standard even if it means having that long rear mud gaurd on the L. Lucky I've got one in good nick as I know and have cut the standard one's down in the past to get a cleaner look.

What was the rise and pull back of the bars on both bikes?

Thanks for any help.

[Gosling1]

going on that compliance plate, I would say you have a standard Z750E1 frame. This is the standard Z750 model. The Z750H1/H2 are the custom model versions of the stock E1/E2 models - they were popular in the US - pull-back bars, heaps of chrome, king/queen seat etc. Poxy. These bikes were sold in Oz in the early 80's but were not very popular so they didn't sell many. NFI what the rise or pullback on the bars was .....

The Z750 was made for a couple of years, 1980/81 the models were Z750E1/E2. The Z750L1/L2/L3/L4 models were made over the same period and were pretty similiar in most respects. They changed to the GPz750 in 1982 and this has a frame number of KZ750R1. This bike is the sporty one, better cams and better suspension - the earlier E-model 750's were just pretty standard bikes, nothing special. The later L model bikes from about 1983 used the GPz cams so went a bit harder.

Kawasaki were covering a lot of bases in the 750 class during this period, as both Honda and Yamaha were bringing out new model 750's......it was a class that had a lot of competition. We didn't see a lot of the US-specific models, in fact I am pretty sure we only saw the E-model 750's in Australia as the main 750-class bike until the GPz750 from 1982-1985.

[hipstir70]

Thanks for your reply Gosling. Maybe I should've put up a photo of the other to show what was confusing me. I know all the E and L's frame and engine no's go something like kz750e-********. What got me is the area circled in the photo's, I have a tank and all plastics for a 1981 kz750 E2 floating around but if it was a 1981 kz750 L1 tank (more squarer shape) which I have and I'm just missing the side covers.

I know the these bikes aren't much by todays standards or there big brother but, they were fairly quick at the time and they responded well with the later model gpz cams and 1mm larger exhaust valve? I don't know if I remember correctly i thought they had a smaller combustion chamber than the later model heads? and these few mods helped them along a bit or maybe it seemed like that as my friends at that point were riding bonnies.
Thanks.

[Gosling1]

I think the sidecovers use the same mounting points, so you should be able to use either E or L model sidecovers. I have 2 E model 750's but now you have identified that other ID stamp on the compliance plate - will check mine to confirm......

The later GPz cams had same timing and lift, but had fatter lobes so the valves opened quicker.....and I think the combustion chambers in the later models were also smaller than the early ones but you would need to have them side-by-side to spot the difference.....not sure about the valve sizes, I thought they all stayed the same in the 750 motor from 1980 right through to '85 ?

[greenman43]

I always reckoned that a Z750E, properly modified with the right rider, would be a game-changer in Forgotten Era. IIRC correctly they were something like 24kg lighter than the 750cc opposition, so probably 30kg-ish lighter than the 9-10-1100s. If you use the same size rims and brakes as the bigger bikes, a very good rider should have the advantage in braking points and corner speed.

All good in theory, but of course I'm certainly not that rider I must confess to at one point looking closely at a Z13 to see how practical it would be to make it chain-drive; now THAT would be a crowd-pleaser in PCRA racing !

Cheers,
Brian

[hipstir70]

I think the sidecovers use the same mounting points, so you should be able to use either E or L model sidecovers. I have 2 E model 750's but now you have identified that other ID stamp on the compliance plate - will check mine to confirm......

The later GPz cams had same timing and lift, but had fatter lobes so the valves opened quicker.....and I think the combustion chambers in the later models were also smaller than the early ones but you would need to have them side-by-side to spot the difference.....not sure about the valve sizes, I thought they all stayed the same in the 750 motor from 1980 right through to '85 ?

Gosling I'm pretty sure too the mounting points are the same as well just a little different in shape.
What I can remember what the mechanic told me years ago when I had the valves lapped & clearances
done one time was that my bike had these mods done. He said it was only a minimal differance in chamber volume maybe a 1ml or there abouts realy nothing and that by what he measured up I had 83 cams again minimal differance 0.5 extra lift but the thing he did say was the most benefit was the + 1mm exhaust valves (not standard) I had as he said that they were a little small standard.
It was my first bike years ago and gave many of my mates bikes a hard time of around that year, thinking of rebuild a bike of my youth so just trying to get the facts and differances right before i start.
Thanks Rob

I always reckoned that a Z750E, properly modified with the right rider, would be a game-changer in Forgotten Era. IIRC correctly they were something like 24kg lighter than the 750cc opposition, so probably 30kg-ish lighter than the 9-10-1100s. If you use the same size rims and brakes as the bigger bikes, a very good rider should have the advantage in braking points and corner speed.

All good in theory, but of course I'm certainly not that rider I must confess to at one point looking closely at a Z13 to see how practical it would be to make it chain-drive; now THAT would be a crowd-pleaser in PCRA racing !

Cheers,
Brian

Hi Brian, I to once thought the same thoughts too on the 750 but I thought it would give away too much on the straights to the bigger bikes and my adbilities to ride.
Z13 now that would be good to see be like the 6cylinder honda I saw getting around PI a few years ago.

Rob.

[greenman43]

Z13 now that would be good to see be like the 6cylinder honda I saw getting around PI a few years ago.

Rob.

Exactly - reading about that was the catalyst for the Z13 thinking

Cheers,
Brian

[Eastoe]

Genuine Z750 manual arrived in the mail 2 days ago and was reading the supplement for my 82 GPZ750.
Horsepower is quoted as 74bhp for the E3 and L2 while the R1 or GPZ is quoted as 80hp.
Cylinder head volume on GPZ is 24.9cc and I think the L model was 0.1cc difference but I can't find it now.
(found it 24.8 but it has a tolerance of 0.4cc so work that one out.)
Compression on Z750 is 9.0 and GPZ is 9.5
Z750 has Keihin CV34 carbs while the GPZ has Mikuni BS34.
Fascinating stuff I know but i'm laid up on the lounge with a bung knee and I'm hard up for entertainment.
Funny that I was reading it last night and saw this post today.

[hipstir70]

G'day Eastoe, my memory v's workshop manual "I know what I'd trust" I know then i've got something wrong somewhere then, it's quite awhile ago now. Another thing I don't recall is if the head was shaved at all, it was still using standard CV carbies.
Found a picture of it towards the end of my time with it sorry for picture, photo of a photo. As i said it was my first bike 1980 kz750e in the late eighties to early ninties.
Cheers Rob.

[Gosling1]

.....Fascinating stuff I know but i'm laid up on the lounge with a bung knee and I'm hard up for entertainment.....

great post Eastoe ! its always good to have the manuals at your fingertips, all mine are out in the library in the 4th, its a pain in the arse going out there this time of year

......Found a picture of it towards the end of my time with it sorry for picture, photo of a photo. As i said it was my first bike 1980 kz750e in the late eighties to early ninties.......

Nice pic mate - looks the goods. Braided brake lines as well, you didn't see too many of these back in the late 80's.....

this is my old Z750 before it started getting.......modified....... - this was back in 1995.

[greenman43]

Z750FX - I didn't know they sold those here ? Is it a Japanese-market import ?

Cheers,
Brian

[Gosling1]

.....Z750FX - I didn't know they sold those here ? Is it a Japanese-market import ?.....

did you mean the blue one or my black one mate ?

[greenman43]

did you mean the blue one or my black one mate ?

Definitely the black one; isn't the blue your basic '80 Z750E (at least, I think that's the model number) ?

Cheers,
Brian

[Gosling1]

....Definitely the black one; isn't the blue your basic '80 Z750E (at least, I think that's the model number) ?....

the black one - well all is not as it seems. That bike is also (well, was) a bog-stock 1981 Z750E. I got it as a wreck and knocked it back together in about 3 weeks - this was well before kids

In that photo, it is using the old bikini fairing from the Black Pearl, a 4-1 exhaust I knocked up myself complete with dodgy Repco chrome turn-out muffler, a set of rear shocks from a 1973 z900 - and everything else OEM.

But the build-quality is so high, I can understand why you would think its a jap-market import

This bike has had a lot of changes over the years......

[greenman43]

LOL, it must be my advancing years and failing eyesight ...