81 XJ750 Seca

Hey there! I've been doing a ton of research on bikes on this site and checking out everyone's builds. I had been searching Craigslist left and right trying to find a good starter bike and finally found one. It's a 1981 XJ750. Got it for $300 and it runs. This is my first bike and I know absolutely nothing about motorcycles but I'm definitely willing to learn. The guy I bought it from says it needs a new rear tire, rear brakes need to be replaced, it needs front and rear turn signals, mirrors, right side battery cover, new seat or patch a small hole, the odometer doesn't work, the speedometer doesn't work, a new battery, the front brake doesn't seem to work, if I pull on the handle it doesn't "spring back" like the clutch handle does, a new front tire and the headlights seem to be weird... The switch doesn't work and there's a actual switch on the headlight. From the looks of it, the headlights or the switch stopped working and they just put a switch on the light instead of fixing it. The engine needs to be cleaned up a good bit too. I plan on doing a good tune up on it and cleaning the carbs and get it running right before I just jump on it and go. I've never driven on a motorcycle before so I want to make sure everything works and is safe to drive. I'm not too worried about the cosmetics until I can actually ride it properly and get it running right. It does have some dings on the tank, looks like from turning too sharp. From what I've read, it looks like its missing some bump stops or something to prevent that from happening. I'm a little intimidated about tearing the bike down and being able to put it all back together again. I'm not too mechanically inclined but I can do some basic stuff. I'd like to have the engine broke down and cleaned out to make sure nothing is damaged or anything. When I first bought the bike, it started right up and sounded ok. The next morning, I had to jump it off and took a bit to start and doesn't sound too great. When I use the throttle, it seems to be sticking cause it jumped up to 5000 rpms and wouldn't go down so I hit the kill switch. I'm really excited about this bike, I can't wait to get on it and go! Enough of me rambling... Here are some pics and a short video of it running.











And here is the video of it...
1981 Yamaha XJ750 Seca

 

Welcome and congrats on your "new" bike. It's good that you realize you have a fair amount work ahead of you. Take your time and don't try any short cuts. Do a compression test and go from there. It sounds like a complete re-do of the front brake system is in order. Rebuild the master cylinder, the calipers and install SS brake lines. Get it SAFE before you hit the road. Don't be afraid to ask questions. There are many knowledgeable folks here who are more than happy to help. Just be patient.
As far as the cosmetics, my XJ may not be the prettiest girl at the dance, But she will turn some heads.

 

Compression test the engine to see if it is worth putting on the road. Rebuilding the engine is usually not worth it on these bikes. If it blows good compression, you don't need to tear down the engine, just proceed with all of the much needed regular maintenance.

$300 isn't a bad buy, but it's going to take at least $600-$800 in parts to make it road worthy (if nothing is wrong). Nothing wrong with learning how to work on the bike yourself, I got my start on my 750 Seca, but be prepared to wait to ride. It'll take you many months to learn how to work on it and do the work (took me 1.5 years because I was trying to make it look pretty for a while before giving that up).

Your front tire looks original too. Check the date code, if it's older than 5-6 years, get a new one, the rubber doesn't last that long.

An old harness like that one will have many electrical gremlins to work out. Likely there's an issue with the headlight relay (reason for the switch) and/or lots of voltage drops in the harness. You'll want to recondition that too and get very familiar with a multi-meter and voltage drop testing.

Your handlebars hit the tank because they aren't original and don't have the proper clearance.

 

Thanks for all the great info! My biggest priority is getting it road worthy. Making sure its completely safe to ride. Parts seem to be pretty cheap from what I'm seeing online, I'll definitely do a compression test. I've seen a few YouTube videos on how to do that.

I'm thinking about changing the headlight out anyway, may go LED or a nice round light. Online, I see wire harness for about $30-$60 which isn't too bad.

I think I read about "Spacers"? Would I need to change the bars completely or just get some spacers?
I've been looking at pictures online and can't tell if the bars are aftermarket or stock.

What's the best degreaser for cleaning the engine? I plan on pressure washing the whole thing to get most of the gunk off it. I've been told brake cleaner is really good. The PO also said it may have a valve leak? Not sure how to check it if it does. I imagine I would take the valve covers off and change the gasket? Again, Thanks everyone for all the info!

 

Also, any ideas on a a good battery or should a generic one be fine?