XJ900 Refresh / Resto

Mods...please move this if I posted in the wrong place.

I was lucky enough to find an original and mostly complete XJ900 on Craigslist in the fall of 2016. I ended up buying a couple of bikes from the same seller and am just getting to the Seca now. I have it up on the lift, have gone over the bike, and am working with the nice gentleman at XJ4Ever to track down some needed items.

I have what I call a small collection of uncollectible bikes that I generally find in need of some repair, fix them up, and then enjoy them when the weather is nice. My main bike is a 2011 Concours that I bought new and now have about 67k miles on it. I also have a 2007 Yamaha FZ1, 2002 Kawasaki ZRX1200R, 2002 Ducati M900S4, and the mentioned 1983 Seca. Of all the brands of bikes I have had over the years...I have probably had more Yamaha's than any other brand and am not new to Seca's as I had a nearly new XJ900 back in 1984, a 1982 XJ750 project, and an 1983 Turbo project.

Back to the current XJ project. It is a low-mile, 2 previous owner bike, and appears to be nearly complete. Sat for an extended period before I bought it, but thankfully it was inside and the owner had drained and filled the fuel tank with race fuel....so there does not appear to be any rust. It looks like most of the parts I need I can get from XJ4 and it will just need a good dose of time and attention to get it up/running. I am planning to pull the OEM exhaust and box it up as it is really nice and I want to preserve it.

Thanks and I will do my best to post updates as I have them.

 

Posting some pictures...

 

Some more....

 

Last couple....

 

Bike is awesome man...

If I ever see one like that I'm definitely grabbing it.

 

Nice looking bike!

 

Pretty nice. What are the plans?

 

Nice !!!!! I'm jealous ....

 

A gentleman named Dave, aka @hogfiddles will want to talk to you about your bike. He has a registry for us delivered 900s.

 

Thanks for all the positive comments! I recognize how fortunate I am to have this bike and will do my best to be a great caretaker while I have it.

No big plans for the bike. I struggle to make changes to collectable bikes that cannot easily be reversed. Although I recognize the XJ900 has not reached the same levels as some of the other bikes of the era (CB1100F, GPZ's, GS-ES's, Interceptors, etc.) I anticipate interest in the model will continue to grow and as a result....I plan to proceed carefully. I just finished a ZRX1200R and I see the Seca in the same light....really cool but they don't seem to get as much attention as some of the other bikes I mentioned.

At present, I am working through a lengthy list of needed parts with the super nice guy at XJ4Ever and hope to get the order finalized soon. I also have a replacement header/exhaust on order (I want to preserve the original system), and then I have a few weeks of work to get it running and safe to ride. I work full time so my garage time can be limited by work, family, and.....upper midwest winter (cold NW wind makes it tough to get the garage warm). First is the front brakes and forks to be pulled, cleaned, rebuilt, and reinstalled. Once it is running, riding, and looking good....I will see how long it keeps my interest.....I tend to get done with projects like this and keep them around a while but I also start feeling bad about having a machine spend most of it's time under a dust cover. I sold a 86 900 Ninja last winter for that exact reason....spent a lot of time on it and it looked super but in the end I was getting reluctant to ride it (parts were about as hard to find as an XJ) and I got an offer from a collector a few states away and sold it in a weak moment. So time will tell I guess.....

Thanks Matt.....Dave kindly reached out and I provided him with my VIN.

Appreciate the warm welcome and the interest in the bike.

 

Smashing bike 1965 Soda.

 

Thanks Franz!

I had a chance this evening to start a more detailed tear down and am attaching a couple pictures. Went pretty well with nothing terribly unexpected found.....although I did end up with another list of parts I need.....I'm worried the patient guy over at XJ4Ever is going to get pretty sick of me.

I do have a question I am hoping I can get some help with from the experts. Before tear down I thought there was play in the steering stem bearing but on closer inspection, those seem fine. However, one of the fork legs has some loose-ness if you will. When I grab the outer fork leg top and bottom and apply some force, there is noticeable play around the inner tube. Any thoughts on what is worn that would cause this?

Thanks for any ideas!

 

Assuming proper fork internal assembly and bolt torques, etc. then worn fork tube bushings, most probably the ones in the lower tube.

 

Thanks for the feedback (along with all the parts help!). Premature I know....but I was thinking it must be something else considering the low miles on the bike but agree with your assessment, worn bushings are the likely cause. I will give those a close look when I get a little time to disassemble the forks.

Thanks again.

 

Man I am jelly

 

Hi gang. It has been a while since I posted on the project progress so thought I would provide an update. Things have been going along more slooooowly than I would like but still moving ahead. Forks have been rebuilt, brake calipers rebuilt, master rebuilt, valve clearance checked, new cam cover gasket and seals, tire reinstalled (previous owners shop had put it on backwards), carbs cleaned and rejetted, OEM exhaust cleaned and boxed up, MAC header installed, cleaning, small repairs done, more cleaning, fixing some issues created from the previous owners shop, and more cleaning, and I test fired it today! Popped right off and settled into a decent idle....unfortunately, I need to apparently double up on exhaust header seals or track down some thicker ones....exhaust leak will prevent me from setting/synching the carbs.

In the interim, I will start reassembling the front suspension so I can flip it around on the lift and finish up the work on the back of the bike. Have not started cleaning the body work yet...just like the rest of the bike, it is a mess of bugs, dust, and dirt (previous owner lived on gravel and it appears he did not own a wash bucket).

Here are some pictures as I stared the partial tear down and inspection;

 

Fork rebuild and final product....I was happy with how they turned out. Hopeful the little bit of 'slop' I could detect prior to the new parts is now gone.

 

Some shots of the OEM exhaust after I gave it cleaning and a bit of chrome polish. It is now safely boxed up and will be stored and kept with the bike.

 

Upon starting to remove the carbs, I found the previous owner or shop they hired apparently muscled them out at some point. The boots from the carbs to the box were not properly in place and the airbox itself had sustained a crack. Thankfully I was able to use a little heat to soften the plastic to get it straightened out and use some of the wonderful plastic weld stuff from XJ4Ever to get it back into usable condition. Carb cleaning and rejet went well. The mixture screws were terribly corroded but I was able to get them out safely and they are now operating nicely (thanks again to parts from XJ4Ever). Sorry about the cluttered workbench....it is not really as bad as it looks in some of the pictures.

 

Last pictures for now....turning the tire around on the rim went easily and the rim cleaned up really nice (I'm going to hold on posting that picture so you can see back on the finished bike). Here is the last picture I took today....most of the bike is pretty clean now and this is just before I hooked up my "test tank" to do the test fire. Aside form the exhaust leak at the head2pipe connection, the motor sounded pretty good.

 

I have a question I am hoping the knowledge of the forum can help me with. As I was going through and cleaning wiring connections, I found the ground cable from the battery to the back of the engine/transmission but I did not see a cable going from the engine/trans to the chassis. Is there a cable and if so, where would I look for that?

Thanks for all the help and for any info you may have regarding the ground cable.

 

typicaly there is a ground from motor to frame.
on 750 there are 2 cables at rear of motor that connect back to frame on left side it is just under the regulator mount panel on the 750

 

the 2 circles may be the grounds

 

Thanks XJ550H. That is where I found the one ground cable that runs direct to the battery....but did not see a second one in that area. I will look again this evening.

Do you by chance have a picture or know of where the chassis connection should be attached on the frame itself?

Thanks again for the help!

 

no I do not own xj900 but the Hgfiddles may be able to help you @hogfiddles

 

Thanks again XJ550H....I appreciate the response and the recommendation to check in with hogfiddles.....I may do that.

I did look over the bike again tonight and I am unable to locate an engine to chassis ground cable nor an obvious post on the frame where a cable would connect. I did recall cleaning a ground wire and post (not very heavy gauge) at the coil. That may be it....if I don't see anything else as I am going over the bike and awaiting parts, I will give hogfiddles a shout.

Thanks again.

 

there isgrounds at the coil some bikes have 1 some have 2 one of them goes back to the voltage regulator connector.

if you look at photos in this thread you will see the motor to frame grounds
XJ750 Engine removal and split - Pictures.

you can see the ground strap hanging off this 900 motor

 

Great find, awesome bike, best of luck on the project!

It may not be the same in the 900, but on my 83 XJ650 Maxim the engine-to-frame ground goes to one of the airbox mounting bolts on the left side of the bike ahead of the regulator/rectifier and TCI units.

 

Thanks Furman and again....thank you for all the guidance XJ550H! I am not able to locate a second ground cable running to any of the attachment points on the frame.

Exchanged messages with hogfilldes and I am attaching a picture of the back of the engine/trans. Sorry it is sideways...that was the only way I could get in close enough with the camera. Anyway, there is just one cable attached and it runs straight to the battery.

Thanks for any additional guidance to help me determine if I am missing something!

 

I don't believe there is a 2nd ground wire on the 900's...............the 650 and 750 models used that 2nd ground wire because the regulator is mounted on the plastic plate, and so I guess Yamaha decided "better safe than sorry" and worked up an extra ground cable from one of the plate mounting bolts to the frame.

Of course, you can always run extra ground wires from any spot on the frame to any place on the the engine case (engine case is good, the point on the engine case where the battery ground cable is attached is best) to try and eliminate any electrical gremlins. Many/most electrical problems are not power SUPPLY problems but rather are "poor grounding" problems. All circuits require both a supply (+12V from the battery or alternator) as well as a ground back to the battery. SUPPLY tends to be more reliable (except for the fusebox!) since there are individual supply wires running everywhere....that's what makes up the majority of a "wiring harness".

Although some components have individual ground wires, a lot of components are grounded thru the frame, or go to common grounds (by the ignition coil mount is one common ground area; whenever you see a bare RING TERMINAL with black wires running to it, well, that's a ground and you should make sure that ring terminal is not corroded, and perhaps remove it periodically and sand down the area on the frame where it is attached, as neither rust, paint, nor powdercoat is a conductor of electricity).

 

Thanks for the response chacal! I feel better now knowing I am not likely missing anything that could cause me some problems. I appreciate your thoughts on the fuse block....I have not opened that but meant to. I now have it on my list to open, inspect, and clean connections.

I can 100% confirm your insight on the detrimental impacts of a bad ground connection! I have worked on several aluminum framed bikes where they exhibited some sporadic run-ability issues. Upon removal of the ground cables I found the metal of the cable hoop had interacted with the aluminum mounting point and although it was tight and secure, there was a layer of material that needed to be sanded/cleaned to restore the ground. Probably less likely with the steel frames on the XJ bikes....but like you said....still a good reminder to clean all electrical connections.

Thanks again everyone for the research and guidance!

 

A little time today to keep the project moving forward. I had to post with something that made me chuckle...even though I ended up wasting some time figuring it out. First, picture of the inside of the fuse block. It really looks good to me.....there even was not much dust inside. Wire coating shows no signs of heat or cracking and the fuse holders also look sound. I cleaned it up and moved on to reassembling the front.



Reinstalled the wheel and rebuilt calipers. As I typically do, give the wheel a spin to make sure it rolls smoothly and nothing seems out of place. I hear a faint clicking sound. My first reaction is the speedo drive or a bearing. Pull the wheel and check the drive, seems smooth in my hands, bearings turn freely and smoothly with my fingers. Hmmm....reinstall the wheel again and give it a spin. Same faint click. Get down to listen at the axle, on each side...seems the sound is coming from the rim area. What the heck....did I drop something in the tire when I dismounted it and reinstalled it to correct the direction? Just about to pull the wheel again and......



found one of the wheel weights was a little loose on it's clip and it was sliding back/forth as the wheel rotated around! Good gravy....although frustrating I pulled the wheel unnecessarily....I am sure glad I did not dismount the tire looking for something inside! A small piece of foam under it and all is quiet.

Hope you all have a super weekend!

 

I should mention....I know I should replace the brake lines and I probably will but I really need to get this thing done and ready for when the weather turns so I can take it for a short ride. I am hoping I really fall in love with this bike like I did with my original 900 back in the mid 1980's. A good friend who owns a dealership called the other day and he just got in a bike I have been looking for and I would really like to say no....I want to keep the Seca.

 

Good afternoon. Thought I was on the home stretch but found a problem. After changing oil/filter, I noticed small puddle under the rear part of the transmission. Oil is dripping out of the weep hole on the bottom of the shaft drive accordion boot. I assume it is likely the rear output shaft seal but wanted to see if there may be another possible cause.

Thanks for your expertise!

 

It could be just accumulated crud/water,minor leakage trapped in the boot, weep hole was blocked until you started messing with things and now it's purging itself. Only way to know for sure is to pull off/peel back the boot and see what's living in there.....

 

Thanks chacal! I did as you recommended and thankfully you appear to be correct. The area around the seal itself looks dry. I will clean up the oil/moisture/sludge in the bottom of the boot and keep an eye on it as I get a chance to get a few miles on it.

 

Hi everyone. In an effort to document the progress on the bike, I wanted to provide some updated pictures. Most of this is the most enjoyable part of the project for me as much of the dirty work is done and progress is more visible as I start reassembling parts on the bike. This is after nearly all of the cleaning is done and I have polished out the painted parts.

Here is the front fairing going back on the bike and sorting through the wiring that flows in/out of it.

 

Air scoops back in place.....

 

Finally....bike right way around on the lift....and I pulled the rear wheel to check the seal and clean the back part of the bike up. Also removed the upper cowl for cleaning....oh the dust and dirt! Still shaking my head about all the smashed bugs on the bike and in every little nook and crevice. :-( Had I known how much effort it was to just get clean....I would have bargained some more on price.

 

Here is the final set of the bike all back together. I was able to ride it down to the gas station for a fill of fresh premium and a short run up/down through the gears. Bike seems to run super but I quickly got cold and had to get another bike on the lift last night before the snow came in today (5+ inches again).









Once the weather warms up and the roads get washed off a bit...I hope to get some sunny day miles on the bike to ensure all is right. May not have an update to report for a bit as my attention turns to other machines.

Many thanks to all who helped me through this process. This is a great forum!

 

Looks brand new !What does that big V8 on the stand fit into?

 

Thanks Matti! Appreciate the kind words!

Believe it or not....that is a Toyota 3.5l V6. We have a little prep work yet to do on it, need to fabricate some brackets, and then it will be going into a 93 Toyota MR2 Turbo chassis. My son says it will fit....because the internet says so.

 

I've heard of that being done, perhaps in an old issue of Sport Compact Car magazine. I can't go check, as my wife sold them all at a garage sale.