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Discussion Starter · #1 ·
OK... I might be missing something, but I searched the archives here, and also poked around for a while at robbynitroz site... I can't seem to find a definitive answer to the following two questions:

-will an `86 750 head bolt up to an 1127 motor and work with the 1127 cams?

-will an `88 750 ignitor work on an 1127 motor, and if so, what difference is there other than the built-in rev-limit? is the advance curve different?

I know that the 1100 head is taller than the 750 head... I also know that the forked rockers are preferred because the shimmed head tends to spit shims... that's a non-issue. My existing 1127 head as well as the `87 750 head are both forked-rocker type. but does the height difference mean that they cannot be interchanged? What about the cam chain? It would suck to hafta split the cases just to swap heads. Does anyone know?

...and the one question I know that nobody has an answer for:

-why do people spend so much damn time, effort, and money working on old stuff?

...well, I kinda do know the answer to that one... if ya hafta ask, it won't make sense.
 

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86 750 head on 1127-direct bolt on? I doubt it.Combustion chambers are smaller,but I'm sure somebody has done it.You can compensate for the height difference w/ taller head gasket

88 short-stroke ignition on 1127?-I had it on mine before the Dyna 2000.It's been a while but I beleive it reaches full advance quicker then 1127.Just don't rev beyond 11,500(if stock)

If your thinking about putting the 86-87 750 on your 1127,don't.It has smaller ports,valves & CC
If anything,I would do the 88&up head.

And as far as why we dump $$ into old stuff?? Simple: because they are proven HP wise.You can hog the bore's out and not have to worry about billet big blocks so the coolant doesn't leak,same thing w/ the head,etc.200 horsepower normally aspirated is common if you got the cash.And pretty reliable also.And besides,everybody thinks that the oldschool bikes are"old,heavy&slow",because of all the new bikes out today and nothing feels better then whoopin' up on some young punk on his new 1000 etc.

[ 10-16-2002, 06:21 AM: Message edited by: oldgixxer ]
 

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fastcat, the 88-89 slingshot 750 head is what you want. as far as i have read, these heads are the only ones that are wide enough to fit on our 1127 blocks. from what i have been told, they can give you around 15 hp just by bolting one on!
the only clearance problems they have is that the intakes are pointed upwards, which means you have less clearance with the carbs. this mod is very popular with the drag racing crowd. hope this helps...
 

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Yes it is the 88-89 750 head you want. Has the same size valves as the 1127 but with better ports. It will bolt on a 1127 but if yours has been rebuilt be sure to check the compression. It can be adjusted by stacking cyl base gaskets. The 750 and 1100 heads are the same height, it is the Block thats taller. And yes the angle is different on the 88-89 750 carb spigots but you should not have trouble with a 1100 but I did have clearance issues on my 88 7-11 with a 88 750 head on it. I could not run "end Pull" flatslides on it as there was no cable clearance and I had to raise my tank for the cables on center pulls.
Bones
 

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ok, there is no height difference in heads. The intake ports between 1100 and 750 are different heights but not overall height. The cylinder block is taller on an 1100 to compensate for increased stroke of motor. To make room for carbs and gas tank clearance suzuki lowered intake port height on 1100 heads. Cams are identical between motors besides maybe lift and duration. Combustion cambers are smaller as is the valves and the intake port diameter on 750 head. If you put a 750 head on 1100 make sure you have room for carbs, airbox, frame clearance issues. Because of smaller ports and valves you probably won't gain much power, with increased compression and increased gas flow velocity the motor will probably have about 100 lbs or torque but horsepower on top will suffer......

The short stroke 750 head of 88-89 is another story. Like they said above its the way to go. Bigger ports and valves allow 1100 to breath good, higher compression increases power.

that's all for now
 

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To add to this thread, I've got a related question. I have an '89 750 that an '87 1052(?) is going in, will the head from the 750 fit and be an advantage? Thanks. Jackie, it was great to meet you on Sunday. Where did you go watch the rest of the races from? You looked great out on the track. Time for some track days next year. Troy 341
 

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Discussion Starter · #7 ·
Originally posted by 341:
To add to this thread, I've got a related question. I have an '89 750 that an '87 1052(?) is going in, will the head from the 750 fit and be an advantage? Thanks. Jackie, it was great to meet you on Sunday. Where did you go watch the rest of the races from? You looked great out on the track. Time for some track days next year. Troy 341
<font size="2" face="Verdana, Arial">We got orange vests and sat inside and outside of turn 4 for the rest of the day (Christine came by in the crash truck a few times and we saw her at the van as we left). I got some great stills from the video-camera down there... if you know anyone who wants digital pics and was racing after about 1:30pm on Sunday, let me know, I prolly have them.

I'm trying to figure out how to keep my streetbike habit and also come up with enough money to get a track bike for next year... My old 1100 is *far* too pretty to go tossing it down on the asphalt.
I was at SB motorsports today drooling over orange-and-grey SV-650's
 

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Originally posted by FastCat:
OK... I might be missing something, but I searched the archives here, and also poked around for a while at robbynitroz site... I can't seem to find a definitive answer to the following two questions:

-will an `86 750 head bolt up to an 1127 motor and work with the 1127 cams?

-will an `88 750 ignitor work on an 1127 motor, and if so, what difference is there other than the built-in rev-limit? is the advance curve different?

I know that the 1100 head is taller than the 750 head... I also know that the forked rockers are preferred because the shimmed head tends to spit shims... that's a non-issue. My existing 1127 head as well as the `87 750 head are both forked-rocker type. but does the height difference mean that they cannot be interchanged? What about the cam chain? It would suck to hafta split the cases just to swap heads. Does anyone know?

...and the one question I know that nobody has an answer for:

-why do people spend so much damn time, effort, and money working on old stuff?

...well, I kinda do know the answer to that one... if ya hafta ask, it won't make sense.
<font size="2" face="Verdana, Arial">
 

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85-87 750 will bolt on but only after cam chain tunnel has been lengthened to match 1100 block,about 10-15 mm (memory not what it used to be) next is compression, cc chamber, this will reduce problem.another problem is gasket sealing surface is small around the front of the cylinders because early cylinder head is narrower front to back. having said that with right work, said combo will make 145rwhp
 
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