first bike, 1983 seca 750, few questions

i bought a 1983 Seca 750 (XJ750RK) as my first bike last weekend and i've been loving it so far, it has 22XXX miles on it and i only paid $800 dollars for it, i have receipts totaling over that amount in work done from the previous owner (clutch, carb sync, stator, rectifier etc). it's not the prettiest thing at the moment, plastic has faded a lot, but the tank and front fender are nice and the bike is mechanically solid

anyway it's running a bit rich, i dont need to use the choke to start it cold. it has the stock air box in it now but the previous owner gave me a set of (used) pods, which im guessing used to be on this bike, from my research on here if you throw pods on you most likely have to rejet the carbs (correct me if im wrong). so i was wondering if there was another solution besides putting the pods back on to fix that (spark plugs are normal)

second, my starter does not like to engage fully when the engine is hot, has no problems when it's cold or even warm but if ive been riding for a while, stop for 5 minutes to get gas and then try to start it up again it will occasionally not engage, does this mean i need a new starter or is that an electrical problem?

looking forward to getting some good use out of this bike, i've already started commuting back and forth to class and work with it and i love it so far!

cheers

 

You need to find the reason its running rich. It may be that the previous owner tried to rejet for the pods and gave up. Only a check of the jets will tell you that. This does require removing the carbs and dissasembly.
Lots of info on here as to how to do it.

Measure twice, then a third and fourth time, cut once.

Research fully on how to do the carbs, of suffer the wrath of the old timers on XJbikes. (better do the valve clearances too, that may placate the ire of the ogres)


If the starter is hit and miss hot, it may be the starter clutch. The starter clutch is a sprag clutch (one way ratchet) and is quite a large job if it is in need of replacement. It is worth trying an oil change in case the incorrect oil is in the bike.

My starter clutch has been playing up for the 7,000klms I have had my bike, and has been put up with due to my intention of replacing the engine with a fully reconditioned unit. A dodgy starter clutch may stay useable for a longish time.

 

Two most important things. Valve clearances and rear brake shoes. The valve clearances are the the most overlooked, and one of the most important maintenance requirements. It takes only about 20-30 minutes even for a novice and is a lot easier than most people make it out to be in their heads. Not to mention, if its a new to you bike, and your having engine troubles, always start with the valve clearances. You just never know.

The rear brakes have a habit of delaminating themselves, and if they come off (Which HAS happened to several forum members) poses a huge safety issue. Pop off that back wheel and look at where the brake shoes meet the bracket and make sure they're not "peeling off."

You DO need to check the valve clearances BEFORE you start fixing/looking anywhere else for the issue you're having. You DO need to check the rear brake shoes BEFORE you start riding.

As for the pods, if I'm not mistaken, they cause a lean issue that's almost impossible to get right. So its possible he had it tuned with the pods on and threw the stock airbox back in which would be why its rich. You'll need to find out if he had the carbs rejetted for the pods, in which case you'll need to put stock jets back in to get it tuned right with the stock airbox.

 

All very solid advice.

In regard to the starter clutch issue: This can be greatly affected by what oil you run. Be sure you're running a motorcycle-specific oil, Castrol 4T is widely available. As long as it's above 41 degrees out, 20W50 is fine.

Modern automotive oils contain friction modifiers that can play havoc with your starter clutch.

 

Welcome to the forum! You'll likely find there's more $ and time involved in this bike than you originally planned for, but stick it out. It's worth the time. Learn everything you can, get the old gal back in serviceable condition and enjoy. These are fun bikes, and once properly reconditioned I think they're just as reliable as new bikes.

 

thanks for all the advice, I'll be checking a lot of these things this weekend. I'd already planned on changing the rear pads and oil/air filter this weekend. I'm not worried about putting money in to it, figure it's necessary with any bike this old, and I love working on cars so I'm up for the challenge

 

BRAKES.

(And in your case, they aren't exactly easy, but not that horrible.)

The caliper and master cylinder seals had a factory-recommended lifespan of two years; the brake lines four years. While admittedly a TAD conservative, at 28 years, you're well beyond any "designed in" cushion.

You need to completely rebuild the brakes, including lines, for the bike to be safe. Check the lines, the date of manufacture is embossed into them. This is a fast bike; you don't want to pop a brake line at the worst moment.

Yes, you're gonna spend some money. To properly "recommission" a 28-year old bike, you're looking at approximately $600~$800 in parts, and that's being careful and frugal. (Go all out resto and you can drop $5 Grand easy.) But if you really want to ride the bike, and use it, and enjoy it without having to fight "problem after problem" then you'll have to do it right. Compare the actually quite minimal cost to that of a new motorcycle, then it makes a lot of sense.

Read this: http://xjbikes.com/Forums/viewtopic/t=24010.html along with the first five or so threads in here, under "Cool Hand Luke" and it will help you with perspective: http://xjbikes.com/Forums/viewtopic/t=27544.html

Believe me, it's possible to sink some time, effort and money into one of these and end up with a virtually new motorcycle at about 1/4 what a new bike would cost; plus the satisfaction of knowing your machine inside and out because you did it yourself. Plus having a virtually brand new 1983 Yamaha is really cool. (Check my gallery.)

GET A SERVICE manual, and rock-n-roll. Lots of good stuff in "XJ FAQ Suggestions."

 

Make your Number-1 Priority acquiring a Yamaha Factory Service Manual for your Bike.
Get the Bible for Seca-750.
The Factory Book is a comprehensive Manual covering your whole Bike.
The Owners Manual come with it, ... in the front.
You'll get introduced to you new bike and get oriented to how it works.
As you need to do things; the Book shows you how in "Play-by-play".

The Factory Book costs more than other Manuals.
But, ... you get you money back.

Stuff you look-up how to fix by yourself saves you 80- bucks an hour when you do it yourself.