My '82 XJ750 "Project Shadow Warrior"

In his last post (4 or 5 posts up), he gives a link to an Instagram page. He hasn't been here since August.

 

Damn, sure could use his help with efi

 

Thanks Brother and I hear you! I was trying to embed my instagram posts on this forum and this site doesn't accept the HTML format, bummer. I did write the administrator if they could accommodate this for us.

chain conversion update: I know I have stepped away for a while, but I'm back. Like others in the past, my pursuit to chain-drive conversion failed. This venture did prove it is possible though. The major road block that stopped me was the oil pump. The way the gerotor oil pump is designed, oil flow is reversed when the engine rotation is reversed. In other words, reversing the engine rotation will make the oil pump back into the sump or suck the oil out of the engine. I researched and only a "one-off" billet oil pump would solve this, way too much $$$$. I even tried to find out who the engineers were on the Japan endurance race team at the time of the 1984 XJ750r (OU28). I ran into the powersport engineers at Yamaha here in Georgia and inquired with them. They told me that Japan shares nothing with North America on instances like this. Translation, I'm smalltime. No big deal, the bikes pretty radical as it is. Maybe someday a super XJ fan with deep pockets will do this, but I'm not holding out. I'd love to see the 1984 XJ750r (OU28) in the flesh though.

Bike progress: Like all of us, life has it's priorities. I have had to start and stop the build several times due to outside factors. There has been a ton of "little things" done since the last post. It doesn't look much different, but a lot of engineering problems have had to be dealt with. I could write a novel here to what's been done. I'm still working out the bug on EFI. I added a cam sensor on the intake camshaft and I'm still trying to work the bugs out. I'm trying to do sequential spark and fuel for individual cylinder tuning. Right now it's running on COP wasted spark and single trigger. Hopefully in the near future, I'll have sequential. I have had a hell of a time with oil leaks from the seal of the turbo. I found out that oil will back flow into the turbo from the pump when the bike is not running. I added a check valve to stop the back flow. The leak still continued. I installed a check valve on the inlet side that requires just over 1 psi to open. That seemed to finally stop the oil from leaking when the bike was not running. The still leaked while running! I then found out that some turbo oil drain tubes can't keep up, so I fabricated a oil drain sump. The oil still leaked! I then read that some internal scavenging pumps create too much vacuum which can overpower the seals and keep them open. I added a vent to atmosphere so when there isn't oil being sucked the pump draws air from atmosphere. Again, oil still leaks! I'm at this point out of ideas? I thought maybe too much oil pressure? But, the pressure is within acceptable parameters (50-75 psi). I suspect there might be damage? None the less, frustrating!



I wanted to see if a 160/70R17 tire would fit and the gamble paid off! I upgraded from a 150/70R17.



I also had MotoGP hand control custom made



The rubber intake runners didn't cut it and fabricated aluminum ones. I had offsets, so I had to use defcon to smooth out the runners. It to FOREVER to sand smooth, but happy with the results.





I have been in contact with a fellow member on here that designed a lockout clutch for our engines and was able to get one!



Here is a few other photos






Motobrain x2



I know there is a lot I left out and I'll try to answer your questions if you have them. I'll keep this updated to the end now. Not too far out. Hopefully before the end of the year.

 

Is there not room to modify the oil pump so that a shorter chain turns a gear that meshes with a gear that replaces the pump sprocket, thus turning the pump the right way when the engine is run in reverse?

 

no It's just too tight in there from what I found. I tried to fabricate bypass tubes to reroute from the backside of the pump, which was successful, but ultimately failed due to warpage of the geroter gear walls.

Here are some photos of my R&D oil pump bypass. You can see were I'm trying to mill out the ports add tubing to that and route to other side. Unfortunately, I don't have a photo of the final result.

 

Hmm.....

External electric pump? You'd need to figure out plumbing, but It might be doable. Might be ugly too.

 

yeah, no thanks. I think the 160/70R17 tire will get destroyed, but ascetically looks decent. It would have been cool to have figured out the oil pump from an engineering standpoint, but economically, it's impractical. I hate saying that! I just have too many battles to fight on this project to win the war. It all started when I threw up a R1 rear wheel to the bike and thought it looked sick.

 

I started on my taillight last night. I ordered a sheet of smoke color Polycarbonate glass from McMaster. I plan to install (3) 1.25" round red LED lights. I ordered a Smart Triple Play from Custom Dynamics to control the LEDs. It uses both turn & brake lights when braking and controls the turn signals











I still need to shape the glass to the profile of the tail. It will also need to be polished to become clear.

 

I also did some metal fab work on the belly pan. I needed to make a fix for the hole I cut out of the pan to let the exhaust fit. I came up with this little scoop.

 

I had a buddy approach me about my build and suggested I rethink my front end design. He thought, since I have more of a classic line from the tail to the tank, the street fighter light just didn't flow. I've been working on this bike for some time now, as you all know, and I know that an outside perspective can be a healthy thing. I came across the Ducati TT1 front fairing and fell in love with it. I roughly threw it up on photoshop to see what it would look like on my bike. I'm digging' it! What do you guys think?

example:


my bike:



photoshop:

 

hah! different and fun!

 

Some updates, more coming soon!

 

Dang....
Looking good.

 

That is impressive. I like your previous headlight that you had on the bike.

 

It's been a LONG road, but I finally got this beast to finally run right! I had a megasquirt guru come by the shop and help with the setup. The project is finally coming into the final phase. The next step is to tear apart and metal finish and paint.

 

Will you be putting it on a dyno soon?
That thing is truly amazing

 

I'm going to be doing that last most likely. Probably be like 6-10 weeks from now. The bike will be done at that point.

 

Ok, since this whole bike build idea all started right here, I'm going to give you all the first sketch of the paint scheme. I don't think I'm going to publish it anywhere else until it's done. An inspired tribute to the OU28!

PS: please forgive my fat finger turbo

 

Finished the bodywork and paint just in time for the Forged invitational. I still have to break the engine in and dyno tune the bike. Almost there, the finish is near! Photos by Silver Piston Photography

 

WOW!!! You have stuck with this build/project for just over six years, at least on the forum that is. The photos are very well done and the bike looks amazing. Looking forward to some videos of the bike once you have it sorted. Bravo!!!!