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Lots can be learned from late 70s- early 80s superbike racing. The GS750 and GS1000 were dominant along with Freddie Spencer's cbf Honda and kz900/1000s. Google Wes Cooley and you'll see what I mean.
 

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Discussion Starter #42
Because I didn't have my Street Rod Technologies class today I couldn't really do any metal work so during my down time today I got working on the tail prototype (used to get the right proportion on sheetmetal/or aluminum version)

Was done pretty easily with just a few tools. A few things could have made it easier and faster. I have seen people use electric turkey knives and it seems to work pretty well so that may have been good to have. Also I know they make some sort of foam file that speeds up the shaping process.

So the sheet of foam I used was 1in thick which made things nice and easy. Took my measurements and squared it all up

To hold all the pieces together I just used regular 2.5in wood screws through both top and bottom. It worked very well.



Final test fit on the bike came out looking almost exactly the same as the rendering so I'm quite happy.

Now the tough part will be transfering all that shape to metal! I need some opinion on taillights. I want to either do a single round taillight or get two smaller round ones and do the dual taillights. Which route do you think will look the best?
 

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Discussion Starter #43
Because I didn't have my Street Rod Technologies class today I couldn't really do any metal work so during my down time today I got working on the tail prototype (used to get the right proportion on sheetmetal/or aluminum version)

Was done pretty easily with just a few tools. A few things could have made it easier and faster. I have seen people use electric turkey knives and it seems to work pretty well so that may have been good to have. Also I know they make some sort of foam file that speeds up the shaping process.

So the sheet of foam I used was 1in thick which made things nice and easy. Took my measurements and squared it all up

To hold all the pieces together I just used regular 2.5in wood screws through both top and bottom. It worked very well.



Final test fit on the bike came out looking almost exactly the same as the rendering so I'm quite happy.

Now the tough part will be transfering all that shape to metal! I need some opinion on taillights. I want to either do a single round taillight or get two smaller round ones and do the dual taillights. Which route do you think will look the best?
 

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quote:
I need to find a good balance of old and new. I want performance. I am slimming my tire options down by going up a size but I feel like good performance can still be achieved. I realize even at the end of the day this won't be able to outperform the street bikes of today but I want a quick bike that will handle on the track without feeling like I need to limit myself entirely because of it's age. Exhaust plan has been 4-1. I want to run the collector dead center under the bike and kink it out between the back of the frame and swingarm. Hopefully the only things getting close to hitting the ground are the crank covers:D In the end it's all for fun and if it can go fast through some turns I'm sure it will scratch my itch. What are your thoughts?
My thoughts depend on whether you are planning to take this to a race track or just keep it on the street. If you plan on riding it hard enough on the street to worry about dragging the case covers then I have no comments whatsoever, since that would be foolish and irresponsible. If you are planning on doing an occasional track day or actually race it then I suggest you follow my ideas about raising the ground clearance front and rear with good forks and shocks. There are a few good 18" race tire choices for bikes that size, but not many or cheap.

Ken
 

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quote:
I need to find a good balance of old and new. I want performance. I am slimming my tire options down by going up a size but I feel like good performance can still be achieved. I realize even at the end of the day this won't be able to outperform the street bikes of today but I want a quick bike that will handle on the track without feeling like I need to limit myself entirely because of it's age. Exhaust plan has been 4-1. I want to run the collector dead center under the bike and kink it out between the back of the frame and swingarm. Hopefully the only things getting close to hitting the ground are the crank covers:D In the end it's all for fun and if it can go fast through some turns I'm sure it will scratch my itch. What are your thoughts?
My thoughts depend on whether you are planning to take this to a race track or just keep it on the street. If you plan on riding it hard enough on the street to worry about dragging the case covers then I have no comments whatsoever, since that would be foolish and irresponsible. If you are planning on doing an occasional track day or actually race it then I suggest you follow my ideas about raising the ground clearance front and rear with good forks and shocks. There are a few good 18" race tire choices for bikes that size, but not many or cheap.

Ken
 

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I have to admit that I like the look of lowered bikes with that drag racing/street rod style. It's perfect for blasting from one point to another in a straight line and for city riding in a place like Chi Town, that can be a fun way to go. Unfortunately they don't go around corners worth a sh!t for obvious reasons - they are too low.

If that's the idea, then forget about sticky tires or cornering ability or tracks. It won't work very well and when the engine covers ground and lever the rear wheel off the deck, the wreck that follows will cost way more than the $100 for Tony Foale's book. The latest edition of his book is 69 euros from his web site. Buy it or borrow a copy or at least find one in a library somewhere and learn more about the subject so you can make informed decisions.

At the moment you have a number of different outcomes in mind and they are incompatible. It's important to get those clear. Low and tough does not work with going around corners fast. Long tanks look very sixties but shift weight to the rear and that hurts handling too.
 

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I have to admit that I like the look of lowered bikes with that drag racing/street rod style. It's perfect for blasting from one point to another in a straight line and for city riding in a place like Chi Town, that can be a fun way to go. Unfortunately they don't go around corners worth a sh!t for obvious reasons - they are too low.

If that's the idea, then forget about sticky tires or cornering ability or tracks. It won't work very well and when the engine covers ground and lever the rear wheel off the deck, the wreck that follows will cost way more than the $100 for Tony Foale's book. The latest edition of his book is 69 euros from his web site. Buy it or borrow a copy or at least find one in a library somewhere and learn more about the subject so you can make informed decisions.

At the moment you have a number of different outcomes in mind and they are incompatible. It's important to get those clear. Low and tough does not work with going around corners fast. Long tanks look very sixties but shift weight to the rear and that hurts handling too.
 

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Discussion Starter #48
I refined the tail a bit more the other day to make it look closer to the rendering

Hung the bike up and got the old fork off

Out with the old races

Here is the difference in each unit. The shaft in the GSXR unit is about 3/16 bigger in diameter and tapers toward the middle. The old bearing races inner diameter is too small for the new unit so I am going to get some custom bearings from Allballs bearings to make it all work. Have all the measurements and now it's just waiting through the holidays to get moving on the project again!
 

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I noticed in your rendering you have clip ons for handlebars. I put some on my gs750 and the stretch was too much for me with the stock tank. I am 5' 10". That stock tank is plenty long and it seems like adding 2.5" will be quite the reach. I ended up switching to drag bars and eventually super bike bars to be comfortable. I guess I'm saying be prepared to change the seat, bars and pegs along with the tank. Hope you have a long torso.
 

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Discussion Starter #50
It's been awhile folks and I'm back. The project has been a year in the making and hasn't gotten terribly far from the last post but I have most of the parts to complete the build. I'll bring you up to speed.
Parts aqcuired:
Kerker 4-1 exhaust
PSR Clip-ons
GS1100 alloy swingarm
78' GS750 wire wheels
2002-2003 R1 rearsets with rear MC
Brembo rear brake caliper
Triumph Daytona 320mm front rotors
2001 Suzuki GSXR600 front wheel bearings

So the bike I feel has gained more of an identity and I'm committed to the finish. I made a great contact who works at a local machine shop that build drill bit (the big ones used on the rigs) so we have tons of metal and machines at our disposal. I am in school for Drafting and Design so I work with AutoCad and SolidWorks. I drew up front hubs that bolt on to the 78' hub and accept the triumph rotors as well as stock 2001 GSXR 600 wheel bearings. The reason I went with triumph rotors was cost, availablity, offset, and most of all they had the correct outer diameter. Basically the whole front wheel assembly now bolts up the the GSXR fork as if it were a GSXR wheel on the GSXR axle. For the rear I will be doing the same thing (making a custom hub) to fit a 2002-2003 R1 rear rotor. I'll then be machining a custom caliper bracket to mate the Brembo caliper to it. Wire wheels and modern brakes all around! I'm stoked because on most builds people only have modern front brakes while the rears get neglected. I'm probably going to end up running 15" Harley xr1200 rear shocks to start out and then we'll see how the bike handles from there and make adjustments as needed. The tank is still in the works and for now I will probably just buy an 82 gs750 or gs1100 tank to get things rolling on the body side. SO lot's of fab work to come but the good news is the build is now full steam ahead with most the parts I need and most the resources as well.






 

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Discussion Starter #51
Just a small vid of the giant lathe doing work

 

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Discussion Starter #52

Just the small differences in dimensions between the new and old swingarm. I gain some length but everything else is pretty close to the same
 

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Discussion Starter #53



Just gettin a feel for the riding position. I'm not a too small of a guy so the reach isn't bad for me at all.
 

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Discussion Starter #54
I haven't posted in a long time but there has been a lot of progress over the last year. It's been slow but steady and things are finally nearing completion. It won't be finished or painted but the bike and mechanicals will all be in order and ridable. Here are some pics of the progress.

Ended up redesigning the rotor spacers to be lighter and better looking. After all was said and done we didn't end up using them but it worked out well because we've been selling them to GS guys all over. They are a conversion rotor to make a GS750 spoked or mag wheel hold a Triumph Daytona 320mm rotor which will then bolt up to a modern GSXR fork and brake setup.


Old vs. New



The use of these parts were not required after some thought and weighing the cost of rebuilding the GS wheels to have lighter and wider aluminum rims. I decided to go all new and adjust accordingly. Warp9 Racing is local and I had them build me these wheels for the bike and they worked out great.
 

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Discussion Starter #55
I started finishing up the rear frame hoop in a slightly non conventional way as well as tying up some odds and ends. At the time I wasn't sure what clearance issues I might have so I got a 520 chain because of it's narrower profile. The rear sprocket wasn't tough to get but the front proved to be a bugger. Getting an offset 520 front sprocket is next to impossible so I bought a 530 with the offset needed to clear the wider rear tire. 530 and 520 have the same profile just a different thickness so with the help of my buddy Ben we were able to lathe the sprocket down to 520 size.


Here is the first mock-up of the new wheels and tires just to see how things were going to look and to figure out braking etc.


Oh and I forgot to mention I came across a newer gs750 tank for a killer deal so I bought it. I always liked the way they looked.
 

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Discussion Starter #56
I chose to put 1994 GSXR rearsets on because I wanted to run a rearset with an inboard M/C plus the lines seemed to fit well with what I had planned. The rear brake was intended to be a brembo monoblock unit but after I bought it and mocked it up I realized it would not clear without a spacer so I scrapped that. Instead I bought a stock DRZ400 Supermoto rear caliper and bracket. Worked like a charm. Then it was just a matter of figuring out a torque arm or bracket to hold the caliper in place under braking. Pics of my solution to come later.


The front GSXR monoblock caliper did, however, clear the spokes. It didn't much matter anyways because I had to center both the wheel and the rotor. Once that was done I machined a spacer that would correctly space the two. O and in case you didn't already notice I went from dual front discs to single-sided. There should still be a significant increase in braking power and feel not to mention the weight savings (which is also unslung weight I might add)





New Shock mount installed solid, then cut for alignment purposes. New shocks custom built for this bike by Y.S.S. Fully adjustable compression damping, rebound damping, preload, and ride height. My stock shock mounts were 12mm if I remember correctly as well as bent so I made my new shock mount 16mm.

 

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Discussion Starter #57
I had the rear end pretty much all buttoned up but I tore it all down and started again. Here are some pics of it all mocked up when it was done the first time. I bondoed the seat plug to smooth out imperfections and make it as symmetrical as possible.


To mount the newer, longer tank on the bike I had to fab up a little bracket. Drilled, tapped, and golden. It works like a charm. The steel was really contaminated so it was tough getting a decent weld on it. Luckily this one is out of sight.


The seat pan after some more refining.
 

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Discussion Starter #58
Here are some news units for some.. new units.



New brackets so I could install a steering damper. For safety's sake!


Did some swinger work. Decided on a rear brake situation that made a lot of sense. Adjustable side to side and front to back. This basically makes it easier for me to still fudge with my rear wheel/chain alignment without having to mess with a t-slotted bracket like the ones that come from the factory. I still may do that in the future but for now this will work great and is proven.
Here is the torque arm. The one on top was one I made just for mock-up purposes and the one on bottom is the finished product.

 

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Discussion Starter #59
I know what you're thinking. "Why didn't he undersling the brake or something?" It wouldn't clear between the shock and swingarm which is where I originally intended it to be, so my next option was to undersling it. It looked AWFUL. The way the DRZ bracket and caliper are shaped really made it looked forced/like an afterthought. Where it is now is great because it clears everything really well and will point the brake line straight forward toward the M/C rather than having unnecessary kinks and curves.


ANNNNNNNNNNNNNNNNNNNND back to square one with the tail/shock mounts..


Did a little fixins on the rearsets because they had holes drilled in them by the previous owner



 

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Discussion Starter #60
The original shift lever and brake lever both had broken toe pieces so I went ahead and found a way to make them bolt up with Warp9 parts :)







Well. . . That brings you all about current with the happenings of the bike. I'm really happy with where the bike has ended up other than the fact it's taken so long to get here. I'm excited to get the tail done. Once that is done I can move onto the body work/rear cowl. Once THAT'S done I can put the engine back in where it belongs and begin finding homes for the battery/electronics.
 
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