XJ 650 4k0 - cafeish build

Then I'll take that as a huge compliment, since it's coming from the great chacal himself

 

Basically, you've "invented" mandrel bending, but you've replaced the mandrel with sand. Sandrel bend?

 

The next time someone makes a seat like this can they please make a mold of the base so they can then knock out fiberglass copies for the rest of us Now to find a piece of 3mm Aluminum

 

I will most likely make a fiberglass seat but for mine, creating a mold would be a great idea!

 

Ok, so it's been half year now and a lot more has been done.... I would say all, but I think we all know that there is always that little something that you could have done

We got stuck at the side panels... So sadly I could not figure a simple way of fixating the side panels from the pressed steel mesh so I decided to use the 3mm aluminium...again.
The frame it self is not made out of straight tubes but they are bent, so if I wanted to make the panels so that they follow the lines they had to be bent, twice with 2 different radius. I managed to get the perfect radius for the first bend over the muffler (yeah, I know - I could have found something more suitable, but the muffler is toast any way). The 2nd bend was tricky because it had to be made so that it converges with the first one, hard to explain but you'll see it on the pictures. Then I made some tabs and welded them on.

Pictures of the panels are still to come, but here are some tabs




Next in line was the electrics tray. I used 0,75 mm thick sheet metal to make it. It's pretty straight forward: measure, take in account that you need to make 2 bends and make the cuts and folds accordingly (it helps if you draw it on a piece of cardboard and try it out), because unlike the ore 80's bikes, the rear part of the frame is higher... Once I made the bends and I tried it out without the welded folds. Then I marked the folds how they need to be placed when welded. I welded them and luckily for me, it got welded up just as I placed it, so it's not crooked and it fit like a glove + the welds did not distort the shape tho the welds are not ''nice'' to look at but they are functional and once I grinded them and the tray got powdercoated - they didn't look half that bad

And for the skeptics, when you take a sheet of 0,75 mm thick sheet metal, it's super flexible and people tend to doubt in it's strength, even when you make the bends it's still doubtfully week, but after the welds are made the tray becomes super rigid and it can hold much more than you'll be placing into it... I made sure that the regulator could fit perfectly and the TCI as well, + all the wires. Because the panel fills out the space under my seat, it also acts like a mudguard

and the aftermath:

 

Next up: relocating the key ignition, pictures of the side panels, lowering of the front end, preping the frame for paint etc., work done on the engine, etc....

 

Looking good.
Compound bends are a pain, no matter what material you have to work with.

Keep an eye on the voltage regulator. Even though it's going to be bolted to a big heat sink, they do tend to get hot and airflow is not likely to be ideal in that location.

 

Yeah, that's one of my concerns, I hope that the tire will provide enough wind to the metal tray to dessipate the heat better... I'll let you guys know if it does not work out since I'll be needing a new regulator

As promised, here are the side panels:

and after sanding with 400, 600, 1000 and 1500 sp:

Ignition relocation:
I relocated the ignition switch to the left side of the frame, right above the head cover.
I was doing the relocation while the engine was outside the frame so I had to guess how much space was there. I used a piece of 3 mm thick metal strip which i cut to lenght and shape so it would go arround the ignition switch round body. Than the made bracket got welded to the frame.

And here it is after i instaled the engine back into the frame:

I also had to extend the wires for the ignition switch, which was not that difficult, I just made a middle link with the same connectors that the xj already had, so if one day I decide to revert the bike to its former self (excluding the rear end) I can do so without any extra hassle, just remove the middle link and return the ignition switch back to the former place.

 

I lowered the front end by 4,5 cm which is - as I read - at the upper limit of how low you can go without seriously compromising the handling. I made 2 metal spacers, 2,5 cm long. I placed one into each fork. The spacers also increased the preload on the springs and in fact made the front end a bit firmer, which I actually liked because the old config felt a bit soft for my taste. I got the other 2 cm by placing the forks higher into the upper triple clamp, because the old clamp has the fork clamps lower than the middle clamp and my new one has all 3 at the same level I had to place the forks higher up to be able to clamp them. This way the front end is lowered and the gas tank and the seat sit on the same line

I disassembled the frame and took it to a professional paint shop to get it powdercoated. The price was professional, the paint job - not so much.... The paint has adhered well but I HAD FREGING SAND in all of my threads which I did not block with screws... I asked them beforehand, should I place bolts and silicone cones into holes that must stay clean to which they replied that they will do it for me... Well once I got home I found out that they placed the cones but left the threads unprotected throughout the sanding process.

Now I had a beautiful black frame which I could not start assembling from the fear of damaging the threads. I tried blowing the sand out, but that did not work because it got compacted so freging well that it wouldn't budge out of the holes. I tried using the bolts and screwing them in and out repeatedly but to no avail.

So how to remove compacted sand out of small diameter threaded holes? It took me a while but remembered - how about the round wire brushes that are used to clean gun barrels to people from the states that might not sound super innovative, but where I come from even the cops go around without guns from time to time. I bought different size brushes and put them into a cordless drill and went to work. I cleaned the threads in no time. Heck I even used this method to clean the threads in the cylinder head when it was off

So the entire write-up could be summed up to this one lesson: HOW TO CLEAN THREADED HOLES? One option is to use wire brushes for cleaning gun barrels

 

Work done on the engine:
I disassembled the entire engine, every bolt, every bearing, cog, shim, plate etc. ... Cleaned everything, inspected everything. I found out that the upper chain slide was toast, it fell apart and was held in place by the chain, one mounting point out of 3 wasn't even connected to the main body of the guide anymore. When I released the 2 remaining holding bolts, the guide fell apart into 3 pieces. So I ordered a new one from the warehouse, but the new chain guide has only 2 mounting points because it also fits the FJ 600.

The cylinders had a Max of 0,4 mm clearance each, so no wonder the bike had such a hard time starting up... I tried getting a hold on OEM pistons and rings, but boy is that expensive + eBay didn't even have 4 same sized pistons and rings. So I did some research on eBay merchants selling pistons and other stuff engine related and I found on couple of forums that the merchant ''Cruzinimage'' sold decent quality merchandise, a few people wrote that they had no problems after installation and running the bike for some time. So I bought a set of 0,5 OS pistons and rings, which cost me the same as one 0,5 piston without rings on eBay at that time.
When I got the pistons they looked brand spanking new, they seem to be aluminium cast and turned on a lathe - to my knowledge anyway
I know it's a risky move but only time will tell if it was worth it.

I took the cylinders and pistons to a machine shop to get the cylinders rebored and honed. Even the grasps that worked there said that to the naked eye the pistons look same as any modern made pistons...

The old pistons ... Sadly I can't find the picture of the new ones...

The slide bearings for the crankshaft were looking good, everything else was looking fine and dandy.

I then:
1. cleaned the cylinder head and cylinder block (outside and inside) + removed all old gaskets
2. cleaned the valve surfaces and bodies
3. laped the valves
4. painted the cilinder head and block i have to hand it to my mother - she let me use the kitchen oven since she didn't like the idea od me making an oven out of cardboard, tin foil and a heating gun
5. changed the valve seals

I might have left out some details, but in general, that's it.

 

After i reasembled the engine, i got a buddy to help me get it into the frame, which at that time was out on 2 wheels and 2 new tires - CAUTION: viewer discretion is advised!

Frame without the engine - here you can see that tank to seat line i was talking about and you can also see my tire choice, some of you will like it, some may hate it but I really couldn't picture any other tires on this build, maybe the firestones but i couldn't find them in my country... Even for these i had to do some diggind arround....

Gas tank was in primer back then but it did look nice with the seat Trying out some lines: ...
Front end - new headlight and chopped fender + the Magura 36 mm clipons.


Before I put in the engine I also:
1. rebuild the master cyalinder
2. rebuild the front calipers
3. changed front and back brake pads
4. changed the special bolts on the rear drum slave arm (mine were tosat)

 

After I placed the engine back in I started to do my electrical work:
I was scared to pieces of the electrical work because the PO did some custom wiring, but to my luck most of it was intact + I have got no clue how to do electrical ''stuff'' at all
So again, I went home, did my research for a couple of hours, once armed with knowledge I went back and I tackeld the problem both hands and feet on the job
I removed the old wire sleeves, checked if all connection worked as they should, I then started to tinker with the wires to see which is for what and I got my things in order. I managed to wire the acewell speedo/tacho/warning lights. I still can't get the tacho to work as it should, I did the LOOP method with 1 Mohm resistor but it does not work as it should... All other warning lights work as they should.
I even installed the license plate light with internal wiring in the plate bracket.

I cleaned the wires and connections of all the dust and dirt that accumulated over the years, I shortened some wires (back end of the loom) and I put on new sleeves (major pain in the ass to do). I placed the wiring back to where it belonged, did some tinkering at the electric tray so the wiring is routed directly into to tray. I got the rear and front light to work as they should, I got my brake switches to work as they should. I got the horn to work (caused some issues, but sorted it out).

You may know that I used LED blinkers and rear light. To get them to blink at a normal rate there were a couple of options:
a.) you use resistors - not good, they heat and they take up a lot of space
B.) get motogadget m-unit, switches - not an option, I rather spend those 500 bucks on the engine
c.) toss the led flasher and use the old ones or buy new ones - nope, it has to be as I want it
D.) find a compatible relay - JACKPOT

I did my research and I found that a company named KOSO has made a flasher relay that works on both halogen and LED flashers, it has a range of 25 to 1 w blinker compatibility (I think). It was 25 bucks but it comes with instructions and from a reputable company. NOTE TO ALL: if you plan on installing it - you need to be able to start the engine, otherwise it will not program it self properly, but once you get the bike to run for couple of minutes the relay figures everything out and makes the damn thing blink like it never blinked before (so - at a normal rate). Picture of the relay.

And a little tease picture:

 

GAS TANK:
I decided on a special matte color - frozen finish from BMW, looks good on a car, but couldn't tell how it would look on a bike And i chose to put on some gloss stripes, but no stickers or wraps, a genuine paint job I went to the same guy that primed the engine and told him about my idea. He told me that the paint job would take quite a bit of elbow grease and a lot of accuracy and that it would cost quite a bit more but he was willing to do it just for the cost of the paint he had to buy, but under one condition - that I help him out with his Porsche project paint job - and so it was set in stone.

Don't have the pictures of the process or the Porsche, but I do have some pictures of the gas tank before the stripes were polished

 

And here it is with all the things put together

 

Hey mate the bike is looking great. It’s the look I’m chasing. Where did you get the top triple clamp from, I be been looking for something similar and can’t find one anywhere. Thanks

 

Hey mate, this looks absolutely fantastic. I want to rebuild my engine like you did (every bolt and nut) but I'm nervous about the cost. can you share how much you paid to redo the engine block?

 

I made it. I measured everything, took on the task of sketching it, learned how to use SW programe and made it there. Then I gave the drawing in the SW file to someone with a CNC machine with a block of AVIgrade aluminium and he cut it out for me. Simple

 

About the costs, that will be a difficult one. And take in account I changed everything that needed to be changed, thigs that were in an OK shape I left...
But a fast and rough estimate in EUROS (I live in europe so everysthing is a bit more expensive, but i'm counting in discounts):
- gastekt set: 90 €
- new pistons 0,75 OS with piston rings on ebay - 180 € - with postage and tax from Japan but not ORIGINAL, searched for info on the merch who was selling them and found good info on him on other forums (HONDA CB forum and KAWA forum) but it's stil a gamble so I'll let you guys know if anything blows up on me
- cylinder reboring and honing to book specs - 60€
- new valve shims - 50€
- new cam chain guides: 30 €
- bolts and other consumables: 30-50€ (don't know the exact cost: the case liquid gasket, moly grease etc....).
- lapping valves - paste + tools: 20€
- 6L of OIL + oil filter - 60 € (you don't need this much, but Since you need to change it about 500-1000 km after the rebuild i bought it in advance)
- paint, oil removal detergent, scrub pads, wire brushes, etc. - 20-30 €

I'm writing this str8 out of my head so i have left something out for sure. And there are things that i will need to change soon:
- clutch plates
- need to check valves again and surelly i'll need new shims
- new cam chain - A HUGE MISTAKE THAT I DID NOT CHANGE IT WHILLE I HAD THE ENGINE OUT!!!!

 

And a VIDEO for all that are curious how it looks now, finished, everything installed and roadworthy.