'83 gs750es overhaul reccomendations requested

[sidd]

After finally getting a new contract, I now have the money to get started modding my 83 750 es. As it stands now, it looks like this:

It has nothing special done to it:
katana forks (the stock ones had problems)
acerbis headlight (front subframe was taco'd in the last crash)
mystery 4-1 header and rebuild yosh can.

I'm thinking about doing the following to it:
89 gsxr front end with semi floating rotors and 3.5 inch wheel
89 gsxr rear wheel (4.5)
stainless brakelines
gsxr derived rs34 flatslides
vance & hines or yosh 4-1
custom muffler (I like welding and machining)
custom gauge cluster and computer (I also like electroncs)

I'm specifically wondering if anyone has put a 4.5 inch rear wheel with a 140 tire on the back of an 83 750 or 700 (i understand the chassis are the same) I'm pretty sure that I had read that billy ricks had done this. I'm also considering putting in a new cam, depending on how hard it ends up being. Any advice on that would be appreciated. One other question that I had was what type of air filters I should put on the flatslides. Instinctively I would put individual k&n pods on, but I do a lot of freeway riding, and have heard not so good things about sideways gusts of wind affecting performance with pod filters.

Thanks in advance for the help, anyone who would like to put in their $0.02 about my plans would be appreciated. I'd like to do this right the first time.
-sidd

 

[oldschoolGS]

Looks like a nice project, I am now installing a 4.5in. rear/160 tire rear combo on my 1983 GS750ED after running a 3.5in rear/140 tire combo for 15 years. Both fit nicely but you will have to mod the rear brake arm to clear both-mine is single sided and mounted on top as the stock one is. GSXR 34 flatslides work fine, mine are from an 86'GSXR1100-I have used V+H pod filters with no problems. As far as cams- I am running a CamMotion G-15 grind-you send them your stock cams and they regring them to the profile you want for about $150. I would do the cams as a set. With the flatslides this will really wake up the bike. Slotted cam sprockets are also needed to dial them in.
The photos attached show the rear end mods- the old photo titled "scan1" is with the GS1150 3.5in rear, 140 tire and modified rear brake arm. Good Luck, Ed.
http://groups.msn.com/SuzukiGSGarage/gs750edbacktolife.msnw?action=ShowPhoto&PhotoID=3199

 

[sidd]

cool thanks!

cool thanks!

thanks for the info, specifically on the cams. I won a set of carbs and a pair of '92 inverted forks, with tripple tree. I'm now trying to find wheels for the front and back, plus various front end components.

After doing more research, I came to the conclusion that yes, the 160 goes with the 4.5, not the 140. I'm also trying to come to a decision about the exhaust. I had planned to have a short can that comes right off of the header, but I was told that that would make my low end suffer, which I'm already not too happy with. I'm going to look into those cams more. They look interesting. Though I'm not sure if i'll be able to wait to have my cams reground. I kinda need my bike to get to work! How hard was the cam installation? I'm not expecting it to ba easy, I'd just like to know what I'm getting myself into. Thanks again, and your bike looks awesome!

 

[oldschoolGS]

I would not say that installing/degreeing the cams is easy. It does take a good bit of time-a factory service manual is needed for the torque sequences and specs. In addition a degree wheel and dial indicator are needed. Do some research-there are books that will take you thru it step by step. Attention to detail is paramont and can make a huge difference in performance. Plan about 2 weeks turnaround time on the cams-send them your stock sprockets and they will slot them also (this makes degreeing possible). I have used 2 of their profiles: G2 which is .330@246 and G15 which is .350@252. Duration on both is at .040 and 110 degree centers are recommended. The G2's work well with slight mods and the G15's with a big bore kit.
Aftermarket cams are also available but cost $300-$400. I would go with the regrinds and spend the extra money on valve springs and a manual cam chain tensioner.
I have had my 83GS750ED since new and am on my 4th major rebuild. These are great, well built bikes which respond well to mods. My bike will be done in the spring-I can't wait to ride it with modern radial tires-it should make a huge difference. Good Luck, Ed.
http://groups.msn.com/SuzukiGSGarage/gs750edbacktolife.msnw?action=ShowPhoto&PhotoID=3334

 

[Anonymous]

I was advised to buy a stock intake cam for a GS1100 (1982) and use that (It just drops in). Wonder if anyone has experience with that. Seemed to work well on the GS750 (1982)

Exhaust - use any quality exhaust header (kerker, V & H). I agree though, you will get MUCH better midrange with a larger canister volume. Many early to mid 90's exhaust canisters are steel and can be adapted to your header. I found using an FZR 600 canister ('93?) worked well - AFTER I cut the ends off, inserted additional pipes between the three chambers and between the first and last chamber, AND cut away the land between the small center pipe exiting the tailpipe and the outer tail pipe. I used a tri-pod configuration to hold the smaller inner pipe. I also opened up the tail pipe diameter by hacking off the tip, splitting it and inserting a piece of steel, then re-brazing the tip back on. diameter went from about 1.75 to 2.5 in in diameter - gained 7 HP on top just doing that.
I liked leaving the inner pipe because it went to the center chamber in the muffler, and the gas rushing around the outer tail pipe tip created some vacuum on the smaller pipe. I could see the condensation on the smaller pipe, so I knew it was working. Was reasonably quiet and had a little rip when getting on it. You get the idea. Have fun. (The old megaphone kerker flowed for S #&@ when I used it - no midrange)

 

[sidd]

Cool, thanks for the info! I've ordered a yoshimura duplex system, which should be here before too long. Hopefully it will fit! Its for a 92-94 gsxr750w, which is the first of the watercooled ones. I had been told to stick to the oilcooled ones, but the engine looks the same. I'm mainly hoping the header fits. The can can be made to fit.

You sorta lost me on the muffler mods though. The only can I've seen the inside of is the yosh that I have on there now. It basically looks like a cylindrical cheese grater. I think I'm going to hold off on the cams, at least until the summer when I tear down the whole bike. I was thinking that I wanted to show the 750 engine some love (cams, pistons, headwork etc.), but I'm starting to wonder if it wouldn't be more worth while to get a gsxr 1100 motor.

You can see a picture of my bike in the "gs700e front end..." thread. You can see that I ended up with a 89 front end instead of the '92 inverted forks, but it is still night and day compared to the stock setup.

thanks for the input!

 

[Billy Ricks]

My bike is the one in the foreground. I put about 60 hours into polishing the wheels and probably 10 into the swingarm. I wish I had a right side view to show you but this is just a shot from our last Hill Country Ride. My pipe exits high. I have GSXR rearsets mounted and GSXR guages. This winter I'm considering a major rebuild and maybe an inverted fork.

If you check Ebay and look at the Yamaha R6 and R1 shocks they have the right type of mounts for the GS. It's just a matter of if the length is right. I believe the RC51 had a similar arrangement. With a little machining a late 90's model GSXR shock could be made to work. Basically just machining a block of aluminum to bolt to the bottom of the shock that transitions to the right GS type mount. I have a '97 GSXR shock I may try it with. I'll probably need a stiffer spring but the damping should be much better than my tired old stock shock. This simple mod might make me change my mind about swapping swingarms.

http://groups.msn.com/SuzukiGSGarage/spring2004texasride.msnw?action=ShowPhoto&PhotoID=2964

 

[Guest]

Re: '83 gs750es overhaul reccomendations requested

custom gauge cluster and computer (I also like electroncs)
-sidd

sounds real nice...I have been looking world wide for an oil pressure gauge (digital) that is a flat panel like the daytona oil temp gauges. Is this something you could help me with. I am at the point now where I am thinking I will have to make one or pay someone else to. They simply are not around. The only ones available are round car style. I have looked into avionics, motorcycle, marine...the works. Non exist any more.

Any suggestions? Thanks.

 

[sidd]

I might be able to help you, though there are two problems. First, I don't believe the gs's actually have a oil pressure sender, they have a simple switch. Second, I'm both working and going to school, so I wouldn't be able to do it promptly. I'd hate to keep your project from progressing. I'm accelerating work on my computer though, so I'll let you know if it looks like I'll be able to do it sooner than later. I'm doing something very simmilar with my bike, so something that would work for your needs might come out as a side effect. I'll keep you posted.

 

[Guest]

I have a pressure sending unit on my bike. The time isn't a concern being anytime is better than nothing at all. I will continue my search for such an item and let you know if I find one but I don't hold out much hope on that.

So forge ahead on your projects and good luck.

cheers.

 

[sidd]

OK, cool. Where did you get your pressure sender? Did it replace the stock switch, or did you have to tap the block? I'd like to have one on my bike, so any info you can give me would be awesome. Thanks

 

[Guest]

the switch came with the distribution block.

 

[ronin1166]

Re: '83 gs750es overhaul reccomendations requested

custom gauge cluster and computer (I also like electroncs)
-sidd

sounds real nice...I have been looking world wide for an oil pressure gauge (digital) that is a flat panel like the daytona oil temp gauges. Is this something you could help me with. I am at the point now where I am thinking I will have to make one or pay someone else to. They simply are not around. The only ones available are round car style. I have looked into avionics, motorcycle, marine...the works. Non exist any more.

Any suggestions? Thanks.

Katman/Sidd,
How about these?
They're intended for homebuilt aircraft.

http://www.jpinstruments.com/slimline.html
http://www.jpinstruments.com/slim_install_primary _rev 2.PDF

"Page 2" of the PDF file has a hole template.

Cheers,
Ted

 

[Guest]

Thanks dude,

bin there done that. They are not rated for rain and so forth. Indoor gauges only and vveerrrrrry expensive due to FAA rating.

I believe thay are also 3 or 4 inches deep so would not be good for a bike. I am looking for a flat panel like the daytona oil temp gauge. It is only about 8mm thick.

 

[ronin1166]

Gotcha. That Kat cockpit is mighty cramped for Bling.
What you really need is an electronics geek (who will work for beer), to determine what makes the Daytona display tick, then devise a tweak to accept an oil-pressure sender input.

I'm not kidding. I'm NOT that geek.
I've met guys that could do this kind of thing. Years ago, I worked on a project which needed a custom VFD display made and programmed. I recall that geek saying it wasn't too tough at all.

Wouldn't know where to find 'em, but I know they're out there. Just fire up the geek-detector and sniff 'em out. Got any electronics tech schools nearby? Or find some kind of E-Geek Forum on the net.

Ted

 

[ronin1166]

Sidd,
I have an 18 x 3.50 rear rim from an 86-88 GSXR750 for sale.
A 140 rear tire is standard for that rim.
Shoot me a PM or email if your interested in it.

Ted

 

[Guest]

Gotcha. That Kat cockpit is mighty cramped for Bling.
What you really need is an electronics geek (who will work for beer), to determine what makes the Daytona display tick, then devise a tweak to accept an oil-pressure sender input.

Wouldn't know where to find 'em, but I know they're out there. Just fire up the geek-detector and sniff 'em out. Got any electronics tech schools nearby? Or find some kind of E-Geek Forum on the net.

Ted

It doesn't seem that difficult to me. its is just software. Another algorithm to interpret the signal. I have been looking for the makings to put one together.

 

[sidd]

an update:
I got the front end on the bike:

Not seen in that picture is the fork brace that I got in trade for making a one off fork brace for a friend. I also got these, traded to the same guy for a set of 36's from ebay:

and, after waiting for two weeks for it to ship from canada, my new exhaust finally arrived:

Its the above mentioned yoshimura duplex race system. Looks to be stainless steel, with 4-2-1 pipes w/crossovers, and quick release header. Compairing it to the stock unit, the header looks like it will definately fit. The midpipe is still an unknown, but I've been introduced to a guy that can do miracles with a TIG welder (I'm not good enough to do exhaust pipes yet)

Along with the front end, I got a matching 4.5" gsxr wheel and hardware:

It came with some fading yellow paint over the stock white, so I spent 5 hours sanding one side until it was smooth, then decided to use paint stripper on the other side. Unfortunately, the stripper also removed all the paint that was smoothing out the pits from casting. Next time I'll get them powder coated, thanks. :evil: I think the paint job came out pretty good for something done with spray cans on my deck. Little known fact: I have a moth wing in my wheel! The little bugger got stuck (probably attracted to the flashlight I was using to paint at night) and I grabbed him off of the wet paint with a pair of tweezers, though his wing stuck. Luckly it was thin enough that it didn't show under a layer of paint

So, I'm waiting on a caliper hanger to go with the wheel, and a caliper. It sounds like I need a katana caliper, so thats what I'm looking for. If anyone knows of one, by all means let me know, otherwise I'll be looking on ebay.

Thanks for all the responses! I'll be sure to update with more news soon
-sBs

 

[Guest]

I've got a kat hanger and I think a rear caliper. I will have a look.

the goodies look nice.

 

[Billy Ricks]

The midpipe looks to be the proper Yosh piece.