Yamaha XJ750 scrambler project

[Twill]

Hey guys,

I have just bought an old Yamaha XJ750 which I aim to fully take down and completely rebuild into a custom scrambler. It's my first bike rebuild so it's gonna be a whole lot of learning as I go and a bit of trial and error so I'm thinking I'll have a whole lot of questions to put up here in the coming months for advice.

My first is the engine rebuild, I was planning on trying to do the whole thing but I was wondering if it would be best to leave the engine to the experts as I'm not a mechanic and have minimum experience with that side of things. The bike has been sitting for over 5 years so I'm a bit hesitant to just put a battery in it and try and get it going.

Can anyone give me an idea of price I am looking at to get a shop to take care of the motor for me? It will need a complete rebuild, sand blast and paint. I can take it all apart etc but do shops prefer just to do the whole thing. I also have no idea what the condition of the motor is.

I'm in the Bay of Plenty if anyone knows someone I can go and have a yarn to.

Cheers

[Kickaha]

The bike has been sitting for over 5 years so I'm a bit hesitant to just put a battery in it and try and get it going.

I'd be doing that first, why rebuild it unless you have to, XJ forum has pretty much all you need to find out on these
http://www.xjbikes.com/forums/

[mossy1200]

Question is the size of your wallet. I had a budget and doubled it without touching engine or paying anyone to do work other than paint job.

[AllanB]

Interesting project.

Me I'd drain the old oil and fill it back up with some cheap motorcycle suitable 10w40 (you'll replace this again once it's run a bit) change the oil filter. Drain it cold before turning over the engine at all - I'd drop the dain plug and let it drain over night.

Side note - there is a school of thought that all oil changes should be done this way as any particles (ie metal) in the oil will naturally settle to the lowest point in the cold oil. Who knows - another internet debate.

Drain the carbs - if horrid stuff comes out they will most likely need a strip and clean. You can purchase produce you squirt into the airbox when running that claims to clean them. Seafoam springs to mind and Yamaha made a carb cleaner years back that had a good rep. Allow for a proper strip down though. Check the air filter too - it may be slowly falling apart - you don't want than shit in your carbs.


Anyway don't pull them apart yet.

Clean out the tank - flush with fresh fuel - again what comes out? If it's rusty there is a issue for later ....

Remove plugs - clean or replace

So presuming you have clean oil, drained carbs, fresh fuel, a charged battery I'd fire the beast up.

Bet it runs :woohoo:

If it's rough it's probably the old fuel gummed up in the carbs.

Get the engine running well before spending any money elsewhere.

And when it is change that oil and filter again.

[Twill]

Alright, looks like I'm going to try get the old girl started!

[awayatc]

Interesting project.

Me I'd drain the old oil and fill it back up with some cheap motorcycle suitable 10w40 (you'll replace this again once it's run a bit) change the oil filter. Drain it cold before turning over the engine at all - I'd drop the dain plug and let it drain over night.

Side note - there is a school of thought that all oil changes should be done this way as any particles (ie metal) in the oil will naturally settle to the lowest point in the cold oil. Who knows - another internet debate.

Drain the carbs - if horrid stuff comes out they will most likely need a strip and clean. You can purchase produce you squirt into the airbox when running that claims to clean them. Seafoam springs to mind and Yamaha made a carb cleaner years back that had a good rep. Allow for a proper strip down though. Check the air filter too - it may be slowly falling apart - you don't want than shit in your carbs.


Anyway don't pull them apart yet.

Clean out the tank - flush with fresh fuel - again what comes out? If it's rusty there is a issue for later ....

Remove plugs - clean or replace

So presuming you have clean oil, drained carbs, fresh fuel, a charged battery I'd fire the beast up.

Bet it runs :woohoo:

If it's rough it's probably the old fuel gummed up in the carbs.

Get the engine running well before spending any money elsewhere.

And when it is change that oil and filter again.


Very good advise...

If it doesn't start after that...don't panic .
You may need to have a look/clean behind magneto cover ,Coils and earths.
Some electric contact spray in your connectors etc also helpful. ..