T8's 750 Cafe Racer Project

Some very nice fabrication sir. It is coming together nicely. Well done. It is going to look really nice when completed. I can't wait to see.

Rear Tank Mount

Happy Thanksgiving everybody!! Last night I was able to finish up the tank mounting situation. I used a piece of tubing I had left over from the rear end of the bike and welded a piece of 1/8" sheet metal to it to cap it off. I cleaned up the weld then inched away at the length on the grinder till I got the tank mocked just right. I didn't know where the stock grommet and bolt went from my last tank so I found a grommet through Fastenal that would work and I had some extra 8mm bolts laying around so I used one of those. I welded the tube in place then drilled and tapped a hole in it. If you do this be sure to drill and tap your hole last because you'll want to line your tank up and get it as straight as you can. Here are some pics. Don't mind the rust or the ugliness of the welds. After a good sandblast it will all look much better. Plus it doesn't have to be too pretty because it's all getting covered up.





Now I can work on the fitment of the seat plug and do a final alignment and shaping. I already have the fiberglass ready to go so hopefully that's the one of the next things to get done.

looks great. what are the rearsets from mate?

They are from a 1994 GSXR1100 I do believe. I have found that there are a couple different variations of this particular style and also one other style with totally different dimensions so if you plan to buy some try to buy them in a set. It will save you a ton of trouble and is worth the extra couple $$ you might save from mixing and matching a set (I attempted to mix and match )

looks great. what are the rearsets from mate?

[Chuck78]

Man, that upper shock mount is a beauty. Also a great idea since that will tie everything together solidly. Good work.

What he said...brilliant! Good work T8.

Thanks guys! I got to it again this weekend. I was able to get the shock mounts all welded in and the center piece cut out and ground down. I'm pretty pleased with the result. The stock/original mounts were bent and the threads were totally messed up so I beefed these ones up to the max 16mm for the shock mount shaft and 12mm for the threaded portion. They welded in nicely and I just couldn't help myself. . I had to put as much of it together as I could tonight just so I could see her standing on her own! I'm prob gonna rattle can the frame just to inhibit rust because I plan on putting the motor back in and shakin' her down even though it's freezing here. I want it all powder coated by spring so the paint is only temporary. Anyways quite a bit of progress. Now I just need to get the tank mount finished up and finish my seat plug. More steady progress to come.

[steve murdoch]

Looks clean and simple, although i know there is nothing simple about it.

[boontonmike]

Man, that upper shock mount is a beauty. Also a great idea since that will tie everything together solidly. Good work.

I got some work done on the bike this weekend. I was able to weld most everything and get things mocked up. I decided to TIG weld because I suck at MIG. I know MIG is supposed to be easier but I guess it's just because I learned to TIG first it's just easier for me. My welds aren't all stacked nickels but they look good enough and I got good penetration.

Here is the part I had Ben make up for me on the lathe. It is both upper shock mounts connected. I'll mock it up as a unit to ensure proper alignment, tac it up in place, weld it, then cut out the center of it once they're in their final places.


The gussets and the rearset brackets fully welded in place



Holes for upper shock mounts drilled


Shock mounts installed and ends with fully cut threads



Quick mock-up of the shocks


Getting close!!


Now I just need to finish TIGing the shock mounts in place and work out a couple minor fitment issues and she'll be on her way to getting all put back together!

Guys

Having spent some time on a heavy supermoto DR400 trail riding and jumping it, the wheels stayed tight and I had no failures.
If you factor in the force of a jump with a plus 300lb pound bike plus rider on the wheels it stands to reason it will hold up on the road.

Great build and machine work!

What do you need? I have one for the N & EN and one for the LN.

EDIT:Here is one for the N & EN. The only difference I can see is the fuel gauge.

Wiring. . . . .

I just pulled the motor out for the second-to-last time before powdercoating and as I sat there and looked at it with all it's wiring I realized it's been so long I have forgotten where just about every wire goes haha. I'm a little overwhelmed. Has anyone found those wiring diagrams useful? I tried finding one but cannot locate my year and model. If anyone has a link to a 79' gs750 wiring diagram I'd GREATLY appreciate it.

I'll be welding this weekend so if all goes well I'll have the shocks mounted up and she'll be standing on her own legs and feet for the first time since the tear down. I'm very very very excited. I'll also finish fabbing the rear tank mount. Once I can get the tank mounted in a stationary position I can finish the seat plug and start the fiberglass work. Lots to be done but the end is near!!

I was thinking of my piggish 750 for the weight... But what you said makes sense. It looks bad ass though. I'm jealous.

Thanks man!

Relax - given the frame you've got and the power you're looking to put through it, you don't need to brace it. there are two 750 race bikes being built local to me and i've said the same to them. They've seen the bracing put into our 1000 frame and neither of them are ever likely to approach the power levels or sheer agression of riding that it sees...
I'll state again my very personal dislike of wire wheels on heavy bikes. yes, i know just what you've used and it's good stuff - no problems likely IMO.
BUT - wheel stiffness is a major part of achieving good handling. The effects of a lack of stiffness however will only show in any significant way at the outer edge of the performance envelope....road use, just watch spoke tension.

Nothing helps someone to relax like someone telling them to do it haha. And I'm not sure you followed what I said correctly. I'm NOT bracing my frame. It was just a suggestion given to me by one of my good buds on here. Thanks for the info though! I'll be sure to keep my spokes tight

[GregT]

I'm kind of partial to the modifying of a frame's rigidity. . I'll be honest, I'm just not smart enough at this point to even say whether it's a good idea or bad idea. I sell fasteners for a living at the moment and can honestly say even while being in an engineering program at school I did not know a bolt was designed to stretch or in other words have elasticity until going through training at work (I'm sure I'll learn this at some point in school haha). I had no idea how over-torquing a bolt could completely ruin it's strength properties and how easily over tightening one can actually be (90% of us do it every time we wrench on something).. Once a fastener is improperly tightened it reaches a point of no return where it is no longer the same. In a critical application it's as good as trash. That being said, I just have no idea all the work motorcycle engineers put into designing a motorcycle frame. They are made to flex under load in certain areas and transfer loads to others. I'd just be worried to over strengthen an area even by a little bit. The load has to go somewhere and it WILL find a weak spot. Who really knows? Shoot, I just need to hurry up and get my degree so I actually know stuff! I do know one thing though and that is that a motorcycle is a fine machine that is designed entirely upon the concept of balance. You can't change anything on a motorcycle without having it affect something else. The intricacies of a motorcycle never cease to amaze me. I guess that's why I love it. Always a challenge

Relax - given the frame you've got and the power you're looking to put through it, you don't need to brace it. there are two 750 race bikes being built local to me and i've said the same to them. They've seen the bracing put into our 1000 frame and neither of them are ever likely to approach the power levels or sheer agression of riding that it sees...
I'll state again my very personal dislike of wire wheels on heavy bikes. yes, i know just what you've used and it's good stuff - no problems likely IMO.
BUT - wheel stiffness is a major part of achieving good handling. The effects of a lack of stiffness however will only show in any significant way at the outer edge of the performance envelope....road use, just watch spoke tension.