XV750 rebuild

[pete376403]

I am in a similar boat, have always seemed to manage to fix the issues when they arise, but the biggest problem is often finding the issue. I have an intermittent short somewhere on the XJ and it is has been a bugger to find. No chance at the moment because it isn't playing up.

I had a Cb750 that used to cut out at the most awkward moments - would completely loose electrical power to everything. Turned out to be a broken wire in the loom where it flexed at the steering head. (this was back in the days when all the wiring went into the headlight shell and was distributed from there). When the bars were turned it was enough to pull the wire and )sometimes) pull the broken wire enough to seperate the ends. But the insulation wasn't broken - it was a bugger to find, but very satisfying to fix.

[Dr Bob]

bob-give alex a ring about your xv --he is building a pretty radical version of one up right now

Who's Alex- is that the mech at Mt Eden M/C? If I don't get a reply here I'll PM later.

Secondly, we are having a garage sale on the weekend and hopefully sunday I'll give starting the bike a go, will post on success on Monday.

[Dr Bob]

Sorry for the first question, I just found a reference to Alex under the discussion of motorcyle mechanics. North Western Motorcycles, will look them up in the book.
Ta.

[FROSTY:Me]

try norwest motorcycle mechanix -4168932
tell alex I told ya to call him

[Dr Bob]

Cleaned the carbs on the weekend, and got it to fire - for all of 5 seconds. At present still rather reluctant, I hope it gets better when I get a new battery.

[James Deuce]

Cleaned the carbs on the weekend, and got it to fire - for all of 5 seconds. At present still rather reluctant, I hope it gets better when I get a new battery.

Excellent!

I nicked your Dewey quote for my assignment btw.

[Paul in NZ]

Oh well, I may as well give this a go...

In no particular order, having rebuilt a pile of old wrecks (mostly british) and a handful of Japanese bikes.....

Petrol Tank...
Sitting with a half full tank of gas for 7 years there is quite likely to be a fair bit of rust or digusting crap in the petrol tank.. I usually remove the tank, drain it completely, bung up the holes and cycle a few bucket fulls of soapy water through it. Chuck a few handfulls of gravel in and give it a good shake up. Hose it all out, slosh some meths through it (soaks up the water) let it dry. Inspect carefully for pin holes etc, usually at the bottom as the water from condensation sits under the fuel and rusts quietly away!

Install disposable fuel filters before hooking it back up.

Carbs
Clean and put in a new gasket set including any O rings under idle/mixture adjustment screws.

Replace dodgy carb / head rubbers. If you can't afford to replace them, use rubber hose.

Oil
Drain it before cranking the bike (too late). Replace the oil filter and (if possible) wash out the sump / oil pressure relief valve.

Crank the oil through the bike before turning the ignition on.... (plugs out)

Electrics
Remove the battery and check it properly. If it is truely rooted the bike will never run properly even with a jump start. Rule #1. You cannot do any worthwhile diagnosis of the bikes electrical system with a rooted battery.

Clean all the harness, check ALL the earth points by removing them, cleaning the contact surface and re attaching, protect with dialectric grease.

Clean the outside of the coils and HT leads, check all contacts.

Exhaust System
The mufflers will possibly be rooted. Condensation and thin metal is not a good look. If they are, the cost of replacement might make the whole project non viable. Up to you...

Once everything is checked....

Push it outside, borrow a fire extinguisher and fire the old girl up!

Then.. Let the serious bodging begin!

Paul N

[Dr Bob]

The bike seems to be running fine now. I had to rebuild the master cylinder because it was full of crap. What gets me though is that it must have been in there when the bike was last running - it isn't just congealed brake fluid. Mainly just cosmetic stuff to deal with soon.

[Dr Bob]

Oh well, I may as well give this a go...

In no particular order, having rebuilt a pile of old wrecks (mostly british) and a handful of Japanese bikes.....

..........
Then.. Let the serious bodging begin!

Paul N

Although I didn't do a lot of this stuff the bike wasn't nearly a wreck. I have had it garaged the whole time and I did put fresh oil (albeit low grade) in it before firing it up. I have since replaced the oil and filter - everything seems fine. I think my main problem will be the electrical connections, but there are so many of them and although they are working at the moment you never no how corrosion makes them play up intermitt.. intermit. now and again.

[Dr Bob]

If anyone was interested.

Got the compliance done last week - piece of cake. I was worried about the noise of the exhast, but apparantly it's not bad (at least at the revs I was doing at the testing station - it's pretty mean sounding going between cars on the motorway).

The only near thing I had was going into work the day I was booked in for the compliance check (it's kindof on the way... really officer) it started squeaking like an 8 foot mouse. Tried a couple of things but it ended up just being the intake manifold loose (this requires the removal of most of the bike to identify correctly ).

At present it is running sweet. Now the real work begins; recover the seat, find a shiny toolbox cover, clean, clean, clean, put bandaids on knuckles, clean, clean, get a new exhaust $$$$$$$$$$$$$

[guzzi_nz]

If anyone was interested.

Got the compliance done last week - piece of cake. I was worried about the noise of the exhast, but apparantly it's not bad (at least at the revs I was doing at the testing station - it's pretty mean sounding going between cars on the motorway).

The only near thing I had was going into work the day I was booked in for the compliance check (it's kindof on the way... really officer) it started squeaking like an 8 foot mouse. Tried a couple of things but it ended up just being the intake manifold loose (this requires the removal of most of the bike to identify correctly ).

At present it is running sweet. Now the real work begins; recover the seat, find a shiny toolbox cover, clean, clean, clean, put bandaids on knuckles, clean, clean, get a new exhaust $$$$$$$$$$$$$

love the xv range had 3 of then 750 and 1000 i dun alot of work on xv

[Chopper74]

HI there,Im lookin 4 a manual 4 my 82 Yamaha XV750. There may be one on here but I havnt gotn round 2 reading everything yet. I especially need wiring diagrams and a fix 4 my bikes notorious starter problem.

[Multiman]

Well done.I have just bought an 83 xv750. Lousy starter noise but ah well! My Carb diaphram is sick, can't get new ones so I'm up for ideas. I need to borrow a right hand side cover to make a mold off if anyone can spare one?

[Odin]

Well done. Just one thing i cant understand :unsure:, how could you leave it for 7 1/2 years
I have just gotten my dirty lille fingers on an xv500 88 and will be doing much the same as you from here on, cleaning, recovering and looking for a nice and cheap exhaust

How about posting some pic's of the beast if you have them.

[Waylander]

Don't y'all check post dates? lol Mutiman you might try seeing if one from another XV will fit. Maybe off of a 535 or 1000 posibly the 1100. As for you Odin I've already made a suggestion on cheap pipes