new to the forum with something a little different

Hey all! Just got my first street legal bike a few weeks back. Grew up riding dirt bikes, racing karts, to doing auto cross and now since I've sold my car I was itching for something fun. Was browsing a Nissan 240 forum (zilvia.net) that always has some really cool builds for sale. I came across this 83' xj750 gone cafe racer and I knew I had to have it. Got it for $2k, runs great, needs a little TLC to be where I want it to be but coming from a mechanical background I'm up to the task. Take a look and enjoy!

 

We're familiar with the bike: http://xjbikes.com/Forums/viewtopic/t=44691.html

Note that the guy you bought it from freely admitted not checking the valve clearances "because the motor runs smooth" and he didn't want to "open it up and release its mojo."

It's going to take a tad more than just TLC. Welcome aboard and good luck.

 

Well he got near his asking price. That was a hell of a good read on the other thread.

 

Thanks for the heads up. So I'm a rather mechanically inclined fella and I knew I'd be taking on some work with this bike. The seller, a very nice gentleman, assured me the bike runs great. Indeed it does...for the most part.

Once I got the bike I started doing some research on what maintenance to be performed and when etc etc. But back to the bike first for a minute.

Turn the key, open the choke halfway, touch the starter button for a second on a brisk spring day and she fires right up. Play with the choke for a minute or two to keep the revs in the right place. First ten minutes of warmup it idles beautifully at around 1,000rpm's. Clutch feels nice, throttle sticks, front brakes are alright, back drum is lacking more than it should IMO. After a little highway cruising with great throttle response and good all around power, you come to your first traffic light...


This is where I notice that the bike likes to idle high once its warmed up. Right around 2500-3000. No "searching idle" just high. Some smoke coming from the front of the valve covers as well. So i filled it up with some fresh premium and a few ounces of seafoam to start getting at the issue. Another fifty miles in and a little tweaking of the idle adjustment and now the bike sits between 2000-2500rpm warmed up.

After some reading on this very informative forum, I came up with an attack plan to get this lady in tip top shape.

-Ordered a new front tire as the original is quite worn and dry rotting.
-Ordered a new set of rear drum shoes as ive seen on the forum of people having issues of old shoes delaminating and coming apart inside the hub.
-Ordered a new valve cover gasket and the rubber donuts that go with the bolts so I can get around to shimming the valves.

Once I do all this, I will then get into the carbs. The bike runs good and I can deal with the high idle for a little while. I plan on doing the valves, then replacing the rubber connectors from the carbs to the YICS box. Might have to replace the YICS box (is it bad if it has cracks in it??) Before I try making myself YICS tool to tune the carbs, I am going to try my luck at colortuning it. Somewhere in the middle of all that work I'd like to get the throttle feeling crisp and snappy again. Maybe new cable and spring will do the trick.

Looking forward to getting some more great information from all you members!

 

seen it. Was a cool read from the PO tho. Hey its a start , good luck to ya man.

 

Get to your valves first.. No use doing any carb work until you get the valves in spec. Once your valves are spec'd then you can start doing the carbs, if you do the carbs first you're only going to have to re-tune, or should I say correctly tune, them after the valves.

I'm not sure what the YICS box your referring to is? I'm guessing you mean your airbox.

 

2000... for that.. holy heck

to me it is like a butterface woman
Good From Far.. but far from good

also do what the experts on here say..

 

PO is a good author and photographer.

 

Valves FIRST, then carbs right after .......

 

And an excellent salesman.

 

IDK, those are the exact same pictures as the original thread...

 

He may have been referring to Obeewon? But yes those are the same photos. Haven't gotten around to taking any yet so I'm using his for now.

Question, for those of you that shim your own valves...do you have a whole kit of shims or what? Can't find any shim kits online and anything close to a full kit is stupid money

 

Personally, I measured the ones I had then ordered the shims after cl finding what I needed. Then I replaced the donuts and the gasket when the proper shims came in courtesy of Len at xj4ever

 

PO = pervious owner

OP = Original poster.

We above (at least I anyway) were referring to the PO.


As for the shims. Measyre to find what you need and then order exactly what you need. Kits are great if you have a shop or multiple bikes, but you'll have a lot of brand new shims sitting in a box if you just have the one machine.

 

apparently BMW uses the same twenty nine millimeter shins maybe I could get one from the dealership instead of waiting a few days for shipping or if I find that the weather is going to be bad for a whole week...

 

Yes, PO.

When my shims were done I first measured the gap with a metric feeler gauge and recorded the measurements.
Then I pulled the shims one by one and recorded their size and position. I verified the marked sizes by actually measuring the shim thickness.
Reinstalled them in same locations.
Then I re-measured the gaps (measure twice, cut once). Verified original gap measurements were accurate.

This way I found that I could do swappsies with my shims and only had to get two 'new' ones.

And obviously verified correct gap after swapping and re-installing.

That beautiful dog you see as my icon photo helped me through it all.
Best valve clearance assistant EVER!
RIP Darla! :cry:

 

Found this - maybe she wasn't the most ACTIVE Valve Clearance Assistant - but still the best!

 

Looks like an ACD? Beautiful dogs, loved mine. He didn't care for my bikes though, my 550 Maxim would run out gas before he would.

 

You will likely find that the throttle tube is sticking in the switch housing. It will be a good time to clean and relube the switches in the housing while you are in there. An easy afternoon task.

Double check all the modifications made by the PO. Some of it looked questionable to me.

Ghost

 

I brought the bike in to a local shop here in queens, JL cycles. Seem to be really chill guys that know what they're doing. I brought the bike in and they loved it haha. I brought it in to get the front tire replaced. Told them to give it a walkthrough to see how good of shape its in. The head mechanic there told me the bike is in fantastic running shape and that it runs and shifts better than most the old bikes they had in the shop which was nice to hear. He gave it a brief walkthrough while I was there...he found the rear shaft seal to be leaking, and that the rear wheel bearing was feeling past its prime. I handed him the set of rear drums i ordered and told him to take the rear wheel off and go through it.

End of the day walked out spending $250 for a new rear seal, new front tire installed, new rear pads installed, new wheel bearing, inspection, and got the throttle action feeling a little better too. Will definitely be taking my bike back to these guys for further work down the road.

 

So they didn't check the valve clearances either.

And we know the PO didn't.

Ignorance is NOT bliss; they only get tighter until it's too late (burnt valve.)

 

Why check valve clearance, it runs fantastic

 

I'm aware about the valve clearances, planning on doing it myself on a rainy weekend sometime soon! Had to get this stuff out of the way first, cant be riding around with a bad wheel bearing, bad front tire, and bad brake pads. I'd rather the bike die than me die. Not easy being a poor postgrad trying to save some sheckles and have fun at the same time : D

 

Sounds like you're spending money on a potential paper weight.. but hey don't take our word for it. Get it done before we have an I told you so situation on our hands. If we're wrong, at least you'll Have piece of mind.

 

Why check valve clearance, it runs fantastic

 

any old bike thats not completely rebuilt is a "potential" paperweight. If I could have afforded to drop the 8 grand and pay the full coverage on a new FZ09 i'd be riding it today, but thats not the case. Gotta work with what I got. If all goes to shit, I'll cut my losses and convince myself it was money well spent for a few months of fun riding and all the thumbs up and attention I got riding it.

Doesn't seem to be going that way though, at least not yet. Unless something catastrophic happens I don't (and neither does this shop) think it won't make it till the end of the summer.

 

Because it will run "fantastic", the valves literally beat themselves into the head. If they're not opening properly you'll burn the head up because you're not letting enough air out, or in.. there's no real tell tail sign that they're tight until the engines burned up. My engine only had 12k miles on it when I got it, one of the valves was so tight I couldn't get a feeler guages under it. I probably would have lost the engine by the end of the season had I not fixed it. Like you my bike ran just fine before checking. Afterwards you could literally hear the difference, there was a nice solid value chatter,on these bikes slappy valves are happy valves.

 

sorry guys, was trying to be funny.

 

don't make me nervous!! lol, yea its definitely high priority to get it assessed, plus once I get the valves right I can get to the root of this hot high idle with tuning. I'll have to post a little video of how the bike idles, the valves are rather noisy...but then again ive never heard another XJ with proper valve clearances idling sooooo yea.

 

Valve clearances are the prerequisite to being able to properly adjust the carbs.

Don't put it off; it's not that difficult (to at least CHECK them anyway) and you could be right on the edge of something bad happening and you won't know it until it does.

Valve clearances: http://xjbikes.com/Forums/viewtopic/t=14827.html

Part Deux: http://xjbikes.com/Forums/viewtopic/t=29209.html

 

sad thing about the 250 you just dropped on it
apart from the parts, the work to change them is
actually pretty simple.. yeah rear bearings are a pain
but you just have to get a bit angry at the old one and
literally beat it out of there
brake shoes can not be any easier
front pads is a 2 man job in frustration
but think of it is a bonding experience

I will admit that Fitz means well, when I brought my
Maxim home.. I was on cloud 9.. but he brought me down to
reality.. why invest a dime if old maintenance is not done
or if the motor needs a simple test done.. a test that can mean
working fine to a paperweight

get the valves checked.. get compression numbers
then you can ride without worrying if it is the last ride you will
take

I took my bike on 130 mile ride the other day.. a ride my roomate
called ambitious and way to trusting..
it is not so much that, when you know you did the work to make
sure you would make it home

 

My commute is 120 miles round trip. Into and out of downtown Detroit.

If I wasn't 100% confident in the bike, I wouldn't ride it to work.

The only way to have such confidence in the machine is to KNOW that everything is in spec and functioning properly.

 

Amen.

I listened, and many of on this forum have not heard from me lately - at least not for advice. Veronica sings like a bird every morning, and she laughed at the winter downtime. I never have any complaints so my new topics are a little boring.

Last week I changed one questionable shim, re-adjusted floats, added new fuel filter, and replaced front brake pads and front tire. Was a light weekend.

I work in a cube, and am not a gear head by any means, but 3 years with this group, and I know my bike can be trusted for any trip.

 

Good man.

I work largely in a cube myself, but I am a lifelong gearhead.

You can add yours to the ever-growing list of justifiably triumphant successful resurrections that came about as a result of commitment and genuinely hard work with XJBikes support over the past few years.

Once it's "there" then some simple scheduled maintenance, the occasional shim and replacing stuff that wears out is all there is. Exactly as it would have been when the bike was new. Even better in many cases.

Thanks for the support.

 

Awesome stuff guys. Looking forward to learning a lot here. I'm going to get to the valves ASAP. It is a blast to ride and I really don't want to ruin that

 

Cheers! That's what I say every morning when I get to work and every night when I get home, and the entire time while on all the commutes and weekend croozes.

Completing the recommended work will make this bike feel like the new one you would drop the 8k on if you had it.

 

Apparently the rear wheel had to be sent out to a machine shop to get the rear bearing pressed out as it was frozen up in the wheel. $250 saved me the frustration of getting it all apart and having to leave the bike out in the rain we've been having and not being able to get it back together due to a stuck bearing. Working on this thing outside of your apartment in Queens isn't the most pleasurable thing. Nothing like the garage my pops has at home I used to wrench on my car at...

 

I took over my basement
in fact I still have to clean up my winter mess
I wish I had a garage to work in
especially in the cold SD winters

 

Having recently doing the valve adjustment on my 650 Seca. I made a drawing of the intake and exhaust, did my measurements, found the sizes I needed and went to the local Honda/Kawasaki shop. 2014 Kawasaki's use 29 mm shims also.

 

awesome thanks, sounding more like it wont be a terribly long operation. Was thinking these shims were a thing of the past and be more than difficult to get your hands on.

 

I forget which member on here
sorry my bad
but he runs a shim pool
do your measurements
then figure out what you need
and contact and trade
it is brilliant
or you can buy the shims for 10 bux a piece
or buy a shim kit for upwards of 100 dollars

 

Hogfiddles runs the pool.

And yup, these bikes take a certain amount of dedication. I moved into my house in December, and the shed door was frozen solid. I got the bike on my porch, and hauled it into my basement piece by piece, and rebuilt every component, only taking time off for work, a bout with kidney stones, and a broken thumb. But as soon as the snow started melting, I was already hauling a repainted frame out to the shed to be reassembled.

And now the bike runs like a dream. Sticking to the scheduled maintenance program, the bike is no longer a headache. This little community we have here is a fantastic resource. Learn, and pass on to others.

 

I am hoping to have mine running again by Saturday
thanks to Len
before I broke it.. it ran like a champ
leaked oil at the valve gasket.. but damn
it is fun to drive
and all the work I did to it, just made me love
and enjoy it all the more