XJ650 Turbo restoration

Hello all, i've just bought a XJ650LJ from ebay for less than i expected (well i hope its a good deal). I was thinking about making it into something different but i've decided to restore it to original.

The bike does have some history that im trying to find out about - belonging to The Combe Martin Motorcycle Collection at some point in its life.

Here it is after i got it home



Ive stripped the plastic down to see what the condition is and started looking at starting it..





here's as it is at the moment, pet lock was jammed, petrol in the carns stinks and is the colour of wee, so im off to buy a fuel filter, oil filter and some fuel pipes....

 

Is it just me or do those forks look shorter than normal Maxim forks? Also they are center axle, I bet they would improve the Maxim handling also?

Anyone rode a turbo and a maxim and compared the turn-in handling??

Thats a nice turbo mate!

Jay

 

It looks like fun and a very rewarding project to. It also looks like the fuse box has been replaced - so somebody has been looking after it!


Good luck an keep posting pictures.

 

Well i started on the bike at the weekend, armed with fuel hoses, oil and fuel filter i replaced the old pipes and got my fingers crossed...! Well it didnt work - there is no fuel to the carbs, bowls are empty..

So i'll be stripping the fuel side down to see whats occuring??



Also looks like these panels are fibreglass moulds - is that usual?

 

Quick question, does your fuel pump work? If that works you should be getting fuel to your carbs. If your fuel pump does not work, soak it in kerosene for a few hours, overnight or a few days. After its been setting apply some 12 volt power to it. If you get nothing, grab a rubber or plastic mallet and start giving it some light to medium raps on each end, it should come back to life. Also if you havent already done so, replace your spark plugs with new ones.
As for the lowers, Yamaha could have chosen a better mounting system than this. This is a major stress point and the lowers crack very easy here.
Good luck with the bike

 

Ditto on the fuel pump, also be sure to clean the screen on the oil return line from the turbo. You seem to missing an exhaust pipe too. It's cosmetic and attaches to the wastegate on the turbo. The brakes on these bikes are pretty bad, the fronts are downright scary, so look into fitting R1 calipers as an upgrade. The front suspension is a joke too, look for a fork brace, and cartridge emulators for the forks. I just finished an 82 LJ and it's a good bilke if you understand the design flaws. Good luck with your build!

 

im about to start again on the bike (got a few problems with a GL1100 that im sorting too) i'll be taking the fuel pump off and the carbs while im there... fingers crossed for success.

 

I have a similar problem with mine, some idiot at a "professional" shop tried to synch my carbs, all he did I think was a bench synch and now my baby doesn't run at all.

 

I just brought one of these home last night. An 82 non running with 11000 on it. It's missing the lower air dam. Tank smells like varnish. This could be a long project.
I read on here about using the R6 fuel pump. Anybody know what year?
I'll get some pics when it's unloaded.
Thanks

 

i think the early r6 pumps are the ones to use - seem to have the correct bend in the fuel line too.. the newer ones appear to be in tank

 

Once you get the fuel pump working fuel will be sent to the check valve. The carbs are pressurized and the check valve returns excess fuel back to the tank. That's why the petcock has the upper line. If this valve is stuck you will never get fuel to the carbs. It will be pumped back into the tank. Also, be sure to have a manual to familiarize yourself with the Turbo system. Well worth the money spent. They are great all around bikes. Very reliable, but must be ridden on a regular basis. If you let one sit, the fuel system will gum up and you can start all over again. Take your time, arm yourself with knowledge, and enjoy the project.

 

Once you get the fuel pump working fuel will be sent to the check valve. The carbs are pressurized and the check valve returns excess fuel back to the tank. That's why the petcock has the upper line. If this valve is stuck you will never get fuel to the carbs. It will be pumped back into the tank. Also, be sure to have a manual to familiarize yourself with the Turbo system. Well worth the money spent. They are great all around bikes. Very reliable, but must be ridden on a regular basis. If you let one sit, the fuel system will gum up and you can start all over again. Take your time, arm yourself with knowledge, and enjoy the project.

 

I think it was from a 02-04 but it won't matter. The part that matters is the pressure (43psi) and the volume. Here's a pic....showing my fabricated mount with the R6 pump. Yes, it was a "in tank" pump but they only mounted inside the tank to save space as fuel pumps are cooled by the fuel running THROUGH them, not the fuel they are sitting in!
jeff

 

Thanks, Jeff.
I've done so much reading on these bikes, my brain is melted.
The two problems I have is gas in the oil and oil dripping out of the turbo.
I've talked to Len about parts for the carbs. When I get that fixed I'll look at the check ball in the oil line.

 

Oops, about forgot the pics.

 

Did you get this off ebay? I seem to remember the "barn" pic.

Not to know anyone but I installed bdesigns carb kits after Brian promised me my money back if I didn't like the kits he had. They worked fine. His kits also include the check valve (FPR) oring.

I eliminated any chance of fuel passing by installing a 12 volt solenoid between the petcock and fuel pump. I wired it to the fuel pump so it only opens when the fuel pump is operating and as you know now from reading so much, the fuel pump only operates when the engine is actually starting or running...worked out perfectly!! The 12volt valve was less then 30 bucks and made for fuel.

I have no idea about oil dripping out of your carbs unless you might have a valve issue so of course you need to check the valve clearences anyway.
They are pretty cool bikes once you have them running right.

jeff

 

I hope I'm not hijacking this thread.
Jeff, I found this turbo locally in Kansas. Acording to the title it was sold new in 85. It does have the power up kit.
And I'm working on it in the barn instead of the garage because of the bad gas smell.
I'm going use a carb kit like yours instead of totally rebuilding them. It will need new fuel lines though. Should I just go ahead and replace the old fuel pump now?
Did you do the resistor mod for the battery indicater?
Did you get the fuel solenoid at a auto parts store?

Thanks
Devo

 

Sorry, I wasn't online for the past couple days, even though my laptop was turned on in the dining room....

I bought my carb kits from Brian at BD designs and while he wasn't cheap, his super duper kit included every single seal needed for the entire fuel system.....but I understand that Len also can supply those for you.

I DID totally rebuild each carb, seperating them from the rack to replace the seals, then rebuit each carb using all new pieces except floats, cleaned the slides per the "clunk test"(very good write-up)realigned and remounted them to the rack then set my floats and sync'ed them......it was no "slam and go" deal. If you do anything less, you'll be riding on borrowed time since each of those little, brittle seals is nearly 30 years old...and if one of them disintergrates, you'll have problems.

I had a bad pump and made the decision to replace it before learning how to free it up. I had just picked up the bike I had bought a month or so earlier and was taking stock to buy whatever I needed in prep for an upcomming vacation where I was planning on doing the restoration. You may decide to see if you can get it working reliabily or you might decide to replace it. I had ordered my new pump by then and just put my old pump on the shelf for a rainy day.

I got my solenoid valve at http://www.dan-marcrvparts.com/12vofuva.html and bought one like the one at the top of the page. Buy the 1/4" outlet valve so you'll pass enough fuel. Don't worry about the 30psi rating....the engineers for hydrodynamics use a 100% safety factor so your 40-43psi will be fine. I got that straight from the horses mouth so you can bank it.

No, I never got around to doing the battery bypass....but Polack sent me a diagram to do it. I just press the button twice each time i start it....

I doubt Rob will get pi##ed at you for hijacking....he's thirsty for as much as he can absorb too.....and we all got to hang together since there aren't many of us!!

jeff

 

well its been over a year - a change of job and my old goldwing and a celica alltrack to fix meant that this baby waited until last week. So i cleaned everything up, checked the fuel pump was working ok, cleared pipes and removed one of the float bowl drains, cranked it over and no fuel coming out of the bowls...

Squirted some easy start and it started up, but only for the few seconds that the easy start gave it. I looked in the manual that Jeff sent me some time ago and it says that there is negative pressure needed to open the valve to allow fuel to flow.. humph, back to the old drawing board!

 

did ya try putting it on prime?

 

didn't think there was a prime on these?

 

yup opposite to RES is PRI

 

Remember this is a turbo he has, not just a regular seca.

 

doesn't mean the petcock valve should be different. still gotta get fuel into system when its cold

 

But since Turbos have a fuel pump, there's no need for a vacuum operated petcock. It's of the ON-OFF-RES variety.

If your bowls are empty, and the fuel system works, there is a fuel circuit relay under your right fairing with a ground bypass wire. It has a female end and sleeve to prevent grounding in normal riding. With the petcock to ON, turn the ignition on. Now you need to ground the wire (fork works). You should hear the fuel pump running.

The relay prevents the fuel pump from running when the bike is not running (alternator isn't providing voltage) or when it gets a signal from the tip-over sensor. But if your bowls are empty, it won't run and fill them so you can start it.

I spent a whole day verifying my fuel system (tank, petcock, pump, carbs) OFF the bike, and it was well worth it. See my thread here: http://xjbikes.com/Forums/viewtopic/p=3 ... tml#359741

 

learn something new everyday.

 

Whoops, sorry, it should be under the LEFT fairing. It's the only relay with an extra wire sticking out, but I can't remember the wire colors

 

Thanks guys, i've found the root of the problem - the carbs are gummed up, i've just removed them and the bowls are black and sticky. So its a strip down!

I've got a manual from Jeff, but its missing the fuel chapter, does anyone have a manual or some tips on how to strip these down?

thanks for all your help

 

Look here, the 650 Turbo carbs ar very similar in design to the ones on your bike:

http://xjbikes.com/Forums/viewtopic/t=31061.html

 

well i had a go today and had to give up, they were so thick in tar that i took the top off the pilot jet, so i thought that enough was enough and took them down to my local bike shop who are going to service them for £35 which is a bargain!

I'll let you know how it all works out when i get them back

 

I've got them back and fitted, all the pipes attached, pump working.. and it started! took a bit of time, but it did.. but then..

The engine started to slow down and i turned it off, fearing the worst.

I notice that the fuel may have run out and filled it back up, now it wont start, checked the compression, that seems ok, check the spark - thats ok.

There only seems to be fuel coming out of the 2 outside carbs from the float bowl drain screw, is this right?

Can anyone suggest anything else to check before i start stripping it down?

 

so i stripped the carbs down and the guy did a really bad job, the set has now been back to him 2 times, but on the plus side i've got taaaaaaking them off and on down to a fine art..

So tomorrow it'll hopefully be the last refit..?

 

If you are trusting someone else to rebuild your carbs, for £35, you are just going to be disappointed unless that mechanic REALLY owes you a favor. It takes hours to properly tear down, clean, and rebuild a set of turbo carbs, and the state you described mean that an entire overhaul is really needed.

I've done it (turbo carbs) and others on this site have too. Doing it yourself is best. And rebuild kits from BDesigns are a really good idea. You won't see an end to "re-fits" using mechanics, it's just not worth their time. And their time = money.

Number of carb installations is inversely correlated to how good of a job you do on them yourself. It isn't the last "refit" until the bike runs perfectly and can be tuned properly.

 

i think i'm learning that lesson, they were really sludged up and a bath was deffo needed.

 

everythings back together - and it started - but not for long now the fuel pump has stopped.. i feel i'll be chasing this bike around for a while!

 

I have now restarted this project, between a XJ750 that I have now sold, so I have managed to get her started - I bought a R6 fuel pump from ebay, gave it some fuel and its started and running...! wahoo!!

So now i'll start stripping it down and replacing the bits I don't like.

First point of call is to replace those dodgy fuses

 

I'm jealous! I want a turbo for a cafe build! nice find man!

 

With a more powerful fuel pump, you'll want to be sure the pressure regulator is functioning properly, or it'll empty you tank into the engine/carbs in a hurry.

I know it's a complete pain, because I've done it twice, but I STRONGLY recommend you wet set your fuel level/float height off the bike, with the ENTIRE fuel system plumbed, including your new fuel pump. You'll fix any overflow problems there, without needing to change your oil constantly and fouling your plugs.

Replacing the fuse box on these old XJs is always a good idea. Also check your charging system output and fix any issues there, as this will kill batteries in a hurry.

 

Oh bugger.. I've put the carbs on, cleaned them and set the floats but not wet set them, as I don't really have a clue how to do that with a fuel pump running.

I might just chance it and se how it goes?

As far as the charging system, shall I put a multimeter in line and test the output?

 

You might be taking the carbs off and on a lot. Chancing it can overflow your carbs in a hurry. Sure you can do it, but from my experience, rushing on a Turbo Seca just ends up more frustrating. I hate pulling the carbs as much as the next turbo owner, but I'd get used to it until EVERYTHING is working perfectly.

You wet set them like any other XJ, except that instead of letting gravity flow fuel to the carb, you use the fuel pump. You can't really use a test tank, because you need the fuel tap with the return port. Use a couple of leads or make a connector to connect the pump to a 12V source (I used a car jump starter). You'll really want to be able to switch it on and off.

What you are doing is two fold:
1. There is an extra 2 psi of fuel pressure, in addition to gravity, that is pushing fuel into the bowl, and the float positioning/fuel height needs to account for this (although I don't know EXACTLY how small this difference is vs gravity only, it may not be a big difference)
2. You are testing the pressure regulator's ability to regulate the pressure of 2 psi. The stock pump outputs 14 psi, and that is enough to overflow your bowls. Your R6 fuel pump likely outputs 20-30 psi.

Charging system should output 14.5 +/- 0.3V, between 2500-5000 rpm on the terminals of a fully charged battery. Anywhere outside that range, and you need to troubleshoot.

 

Hmm - sounds like a right pain to do.. oh well - i'll have a go never-the-less, I love swearing at the carbs..

 

Watching this thread closely, starting on a resto of my 83 Turbo veeery soon..

Ryan

 

so now I have set the carbs up and plumbed it all back in, started ok with a little choke, but now the revs build really slowly until around 4k and then its fine, between 1 -4 the revs are slow to build..

any ideas on what this could be?

 

in neutral or during cruise?

 

this is in Neutral .. I think it may be fuel starvation?

 

so I thought id ignore the starting problems for now and check the rest of the bike. Started with the exhaust, seems solid, but I only have one side. Downpipes are a little corroded, but not too bad, collector is all together and the turbo looks like its ok... except...

the oil lines have been blanked off...?????

So I wonder what sort of state its going to be in??

Now I need to find out how to re-establish these and why they aint there??

 

I've now found another XJ turbo, that I will be picking up this week.. hopefully i'll be able to build one out of both... and do something fun with the bits that are left?

 

Wow I can't imagine the state of the bearing in the turbo after running who knows how long without lubrication. Hope you can get 1 together out of the 2, you will certainly enjoy the thrill of boost when it hits!

 

well I picked it up.. here it is in all its glory..!!

 

well I swapped the turbo from the picture above and the downpipes to the new blue turbo and with a little persuasion it started!! Happy days.

Now i'll strip it down and use all the parts I have to make one bike..