Pumba the XJ750 project

I suppose it is fair to post a milestone in a project.

Exactly six months on the road and Pumba completed a Far Ride and is now an official member of Farriders (1000klm in 24 hours)

 

After finally obtaining some 32mm throttle bodies, I am working on different options of fitting them manifold wise.


First idea is to use adapter plates allowing easy match porting.














I think this set up could be prettied up and work quite well.

 

i love the look of an EFI setup, i think that this will endup being something that i'd look at doing. Seeing as i dont think i'll ever sell my 900, its not going to be a waste of coin.

Still loving this project, keep it up!

 

More of an update on here soon, but I had to post up this;

 

You sure do enjoy th tech' side of it all, th bike looks good and it should fly with your mods. Th kit is th ebay one i presume, is that a riser i see on th bench, bought or home made, i'm after some about that size.

 

Yes!!!!

 

Riser was a bought one from ebay last year. No longer needed.

Update with manifolds version 2.0 they should be finished next week.

Before;



during;







Pumba project turns 2 years old this week, one year of that on the road only 7,000klms so far.

 

thats beautiful man, keep it up

 

backtracking a bit. How wide are your bars and did you get them to stop hitting the tank with your risers?

2nd, did you just sand blast your whole motor?

TIA and it looks great!

 

Gave up on the drag bars to get licensed and never went back.

Motor was only degreased. The 820 big bore motor I'm about to start assembling is going to be vapor blasted if budget permits.

 

We now have new manifolds.



I managed to achieve 1.5mm internal taper so it matched both the throttle bodies and the intake ports much better then the original factory manifolds.



I like the look.



You are looking at way over 20 odd hours of work (I have lost track), a real machinist with all the right gear and knowledge would have done it in a fraction of the time



Throttle bodies can now be connected with 2" silicone hose and clamps.



Perfect alignment of centres. Measure 20 times, cut once.



Very happy with the outcome of many hours.

Stay tuned for more soon.

 

Inspiring attention to detail, great build man.

 

Very cool. Beautiful work

 

Ok Darkfibre u have way more tools than any regular home mechanic does plus a lot more time on ur hands which tell me ur a single or divorced and have no kids plus u r not latin at all because of all this time u have to dedicate to pumba. That being said I would like to see a picture of how u did or how u intend to do with ur tank to fit the Fuel pump for ur EFI project please.
And also what kind of pump u used or will use?
Thanks

 

Yea man, totally cool, insult people then ask for information!

 

insult? where is the insult? I just mention he has a lot of time which no married guys have is that an insult? or being single is an insult? Good for him he has all that time I would love to have my kids grown up to have all that time and be able to accomplish projects like that but I am way to busy raising kids and take care of wife which in my case is a hands full.

 

BTW if thats an insult I am sorry.
Where I came from the only way to insult someone is saying something about his mother.

 

Time on my hands? This project has been going on for over 2 years, and the EFI system for close to 12 months. I spend less time on the bike than most people spend watching television (which I don't).
As for the fuel pump, I intend to get a unit from a Honda Rincon (same as Gennro has). According to the Microsquirt forums it only draws about 2.5 amps, and comes complete with a swirl pot assembly. The tank will feed the swirl pot via the original lines.

 

So u telling me u gonna mount this pump outside the tank? Good to know. But the ones i saw that on ebay didnt look like it goes outside they were way too dirty to be installed outside lol.

 

BTW still more time than me my wife doesnt let me spend any time on anything when shes at home lol

 

Those manifold are a work of art... Love the direction that you are taking this old beast!

 

I am wondering how much extra gas mileage and HP u gonna get after finished.

 

Silicone hose turned up and the throttle bodies now stay put.

As the throttle bodies are mounted further apart than the FZ6R that they came off, its time to make spacers and extend the linkage between the 2 throttle bodies.

This is the gap;



Easy to make spacers, but the throttle arm extension ended up a bit different as I wanted to avoid flex.



Because of my concerns with throttle linkages coming loose, I used spring washers and locktite and then put heat shrink over the lot. If it comes loose, it has earned the right to.



Upper and lower spacers fitted;



Linkage closeup





820 big bore kit and barrels are at the machine shop for boring and honing

 

New bits


Hope to have the microsquirt driving the ignition coils in the next week

 

So nice! There is nothing better than raw material machined into something like you have done here! Your bike has come a long way, and now it is being sent into the future! It was a motorcycle stuck in its own age, but now it has met the 2000's!

 

I want to know what kind of dog is supervising this project......

 

the feline kind.

Following along because I love these kinds of builds. I have another friend in your neck of the woods that has his own milling equipment and built a 350hp LPG power Toyota Supra pretty much from scrap. Cant wait to see what you make next.

 

Sometimes ideas don't work, so here is a limited edition soon to be changed idea.





I will be running 4 coils, two will fit in the original position, and 2 need to be mounted elsewhere.

Not happy with this set up, but it may be used for a short time.

Next update will be engine rebuild stuff.

 

More pics of things happening;

Same old, same old;



something new;





And it fits;



Now a nice thing about setting up the ignition with the Microsquirt ECU is the fact that the ignition offset is adjustable.
If the missing tooth is set incorrectly in relationship to TDC, you can just adjust the programming accordingly.

Time to weld both together.

 

I think the coils above the valve cover are bad azz, it looks like how they are on the GM LS v8s.
All 4 down there would be sinister.

 

ECU case project



Wires have silicone insulation, not vinyl



Final assembly (after it is running and all clear of bugs) will have heatsink grease underneath the main switching drivers and be encapsulated.

 

Now that is just too groovy! Nice work!

 

Excelent job Darkfibre you r way above the weekend mechanic I am. And for that reason I think I will have to give up my idea about moving to EFI I am way less skilled than you so I would never been able to do things like that. You job is professional grade

 

Please don't be discouraged from doing a conversion by looking at my project.

Some people dedicate time to their hobbies and go a bit far, be it gardening, painting, pigeon breeding or computer animation.

Using my ECU housing as an example, it is what I visualized, and hopefully it works OK. For $150 more I could have bought the ECU in a sealed factory case complete with a wiring harness.

I also intend to over design the air cleaner assembly, which may or may not work in its first version, but it will be aluminium

My project goal is not just to put EFI on Pumba, but to combine it as part of the full project and hopefully not look like a quick addition.

 

Darkfibre, you must be a Engineer by trade or some equivalent talent eh? I like your work and the direction you are heading but just how much is all of this costing you on this make over? Is this not beyond the average persons price range? I wish I knew more about these things myself but to be honest I am old school. Since black and white computer monitors I have built my own computers ect. but I can see you are way beyond that sort of thinking for sure. I remember the first XJ Seca 750 I saw, the first thing that went through my mind was the head design, made me think of the old Chrysler Hemi and then made me question just how much could be acheived by re-making the 750 with todays technology? I think you are headed down that road. It will be interesting to see just what you end up with in Power, and reliability. grunt007, 81'XJ Seca 750R

 

My only qualification is as a motor mechanic, but most of my career has been in EFI and vehicle electronics with a few years as an instructor teaching EFI to mechanics. Also spent a few years in IT up to CCNA level.
No machinist training, just had access to the gear and decided to wing it.
Currently I repair ECU's and do phone support for mechanics that need diagnostic assistance.

As for cost, my budget is imposed at $300 per month including buying tools or equipment. Without the budget restriction it would have been finished more than a year ago. I think the finished project will probably be 4 years and $12,000 there about.

 

Hmmmm...If a hundred of us put up cash,how far could the price drop? I'm not looking forward to cleaning my carb's every year or two.I'm a recent returnee to motorcycle riding( wife is now ex-,kid is "grown" and on her own).So riding is again a part of my life.I'm even thinking about moving far enough south to ride 10 months/yr.With the inevitability that fuel WILL have more etoh in it (got to make corn-agribusiness happy,after-all)and if I want a shaft-driven upright riding position non-German bike,then everything which can be done to extend the riding-life of my machines will pay itself back in HAPPY-time.I'd gladly lay down a "few" thousand(3-4,000) for a chance to have my own "Back to the Future" Bricklin-stylee SECA.After all,I've spent many thousands on my bicycles,what's a few more for my motorcycle?.I alternate two wheel mode of commuting,hate to admit it but I have WAY more fun on the SECA and I've never returned from an XJ ride red-faced,and gasping for air.(NOT that I'll give up the self-propulsion mode,however the farther I get past 50,the harder it has become).Any way,how feasible would limited mass-prod. be?

 

Just a mention that the EFI system has cost only a fraction of the Pumba project. Still well under $1k and that includes buying the rotary table to make the manifolds. Time spent is a different matter.

If I was doing a set up that could be scaled up for a limited production run, I would do it differently, and try to use off the shelf items and avoid the custom one off items.

In theory the manifolds could be mass produced, and a single piece ignition trigger wheel as well.
I think a direct bolt on trigger wheel for an XJ bike would be worthwhile for people doing a project if only due to the fact it could be provided with ECU settings that would save people a lot of set up trial and error.

With an identical trigger wheel, manifolds, throttle body, coils and air cleaner the ECU would work with a copy of a previous tune, with fine tuning needed for different fuel pressure or exhaust etc.


Question is premature until I have a finished system.

 

A decent update is overdue, but here is a pic from last weekend at the staging area for a charity ride



I am not in the pic

 

Finally worked out some better coil mountings.

1 + 4 are on top of the rocker cover;


Mount plates still need to have the corners rounded;


2 + 3 will mount up under the tank in the original position;


Somewhere about there;


Just waiting on the connector plugs and its fit up and test time.



No more Original coils or TCI unit

 

What front end/wheels did you use and how much effort to graft them onto the 750 Seca steering head/final drive?

 

The wheels, forks and diff are all from a Australian delivery XJ750P police special. The fork part numbers actually match a XJ750D (EFI Japan only market)

 

OK - thanks. I was hoping that 650 turbo-like wheel/non-leading axle front end combo would be available in USA-spec'ed parts too.

 

GM LS1 coils fit and clear the tank





Once the connectors turn up (almost 3 weeks wait so far), its time to fire up the Microsquirt and finish programming.

(And round off the mounts and make spacers instead of stacked washers)

 

825 big bore engine is ready for final clean up and assembly.

New bearings are in spec;



So now its clean and paint.



Then assembly

 

WOW.

jus went through the whole build - excellent work man, your cnc work is great as well, as the knowledge to make nothing into something is just impressive.

I will deff be watching this from now on, thanks for sharing with great pictures and explanations!

Chris

 

Update;
Behind schedule on everything in life including Pumba.

But committed myself to a farride tomorrow that will be the old engines swan song.

Minimum of 1,000klms tomorrow (a short version of the iron butt ride the USA does).

Plugs changed, gel seat cover on and fingers crossed.

 

Hope it all goes well and you enjoy th ride, my longest day was Eucla to Kalgoorlie on a CB750. I was heading for my girlfriend at th time so had a bit of extra impetus. I was looking at th farride site just before checking on here...

 

Overdue update.

Bottom end is together and cases tensioned up.

Final parts list done and sent to xj4Ever (len).

I have given notice at my job of 7 years and will soon be an Apprentice trainer of Mechanics, so a lot is happening.

Pumba is about to get a big injection of funds (I had 8 weeks holidays owing).

No pics of the engine assembly due to my Pentax DSLR being stolen out of my car.

But for those following Pumbas build, the engine;

Low KLM police engine.
Full gasket set.
new primary chain and guide
new timing chain and front and rear guides
6 new main bearings (all in spec now)
Wiseco 820cc forged piston kit, bored and honed to suit.
light head surface and light valve lap in.
new starter clutch (rollers/springs and whatever)
new oil pump chain
new oil level window
new clutch pivot shaft bearings and seal
Spin on filter set up
new clutch pressure plate pushrod/bearing/washer
Numerous dowels and seals

I WILL be doing a base dyno run on the old engine, and WILL be doing another run on the new engine after a decent run in.

So May is the month for the new engine, and panniers for long distance running.

Pumba, on the road for 18 months and 10,000 klms, Zero breakdowns.

Now we get serious about some distance.

EFI is still happening, and may be set up on my spare frame with the old engine first. (if the old engine survives the dyno run)