crosspost of an old reddit post: https://www.reddit.com/r/SVRiders/comments/7yt9kt/mandatory_mods/
Another topic that often comes up... what "MUST" I do to a bike I just bought. While this is somewhat an opinion, here is the stuff you really really really should consider. 2 parts here: basic maintenance and basic mods
Track guys, you need to be in a different thread cause your requirements are totally different...
please don't turn this into a religious argument, i haven't gotten the paperwork for the hamster yet...
Let's break these down a bit
here's the deal, your tires are the only thing that's letting you brake and turn (yes, accelerate too, duh). Also the main thing keeping you from sliding down the road on your ass. Old (read the date code), Worn (duh), Dryrotted (shudder) etc. are not going to grip well, are not going to flex well, and are not going to handle water well. So like when you're 16 and trying to get some... be safe, put the rubber on...
while not strictly safety equipment, it works with everything else. A loose chain is going to flop around and feel SOOOO weird. A rusty chain is going to jerk around. A tight chain is actually going to stress your transmission countershaft. So adjust it, clean it, or replace it. Rivet master links are harder to do, but bloody indestructible
You need to see and be seen. And to signal your intentions. If any bulbs are burned out, ffs replace them. Also, stay away from the ebay chineseum smoked integrated tails and dim leds. They're just hard to see during the day in direct sunlight. I can't even count the number of times i've seen guys on group rides almost (or sometimes actually) swap paint because the blinker of the guy in front was hard as hell to see
Remember how tires prevent you from sliding on your ass? Well brakes prevent you from smashing your face into things (YMMV). Good pads, rotors, fluid, LINES, and clean calipers go a long way in preventing face smashing. Really, almost any bike you get you WILL need to clean the pistons, lube the slides, and bleed the brakes. Because ever damn bike on craigslist has 10 year old red brake fluid (hint, it turns red from being exposed to water, red is BAD). Some you may need to rebuild calipers or master. Braided lines are a REALLY good idea, but at the very least replace the rubber ones. They're wear and tear items, and 10 year old rubber just isn't a good idea. So spend a few hours and a few bucks, and don't smash face into things (unless that's your idea of a good time, then JUST SEND IT! and post vids).
I am not trying to get into a religious argument over what kind of oil to use. But either way, change it. "previous owner" tell you that he just changed it? F that guy, he's a liar and dropped everyone's bike. Change it anyway. Cost you like $10 and another $10 for the filter.
Same with coolant. I've YET to see a bike where someone has actually ever replaced it. Just do it, it's easy and smells...awful. I don't know why I went there...
"Crunchy" levers, or snaggy loose cables are bad. mmmk? lube the bolt holding the lever, adjust (maybe replace) the cables (note that all the cables except the choke have 2 adjustment points, a "fine" adjustment up top by the bars and a "large" adjustment at the bottom. Also lube them. Everything is better with lube.
Remember that whole, not sliding on your ass and not smashing your face into things bit? Well your suspension helps BOTH.
if there is a mandatory mod, it's a close contest between suspension and braided brake lines. Do both, and you literally don't NEED to do anything else in the way of upgrades (everything else is personal preference, but suspension and braided lines actually make a huge difference in safety).
If you're heavier than a 5th grader, you probably need a spring replacement for the front. Sonic or Racetech are good choices, but that's cause I don't know anyone else. Or maybe you're baller af cause you got a clever tip on r/wallstreetbetsor r/cryptocurrency and wanna spend a pile of dough so then ak20 cartridge swap, adreani (no idea if they're any good), twf gsxr carts, gsxr swap, whatever. Main thing is though sprung and valved to your weight too heavy and the bike destabilizes on bumps. too soft and the bike is sketch city in turns and under heavy braking. Use a calculator on one of the sites to figure out what your spring rate should be
And some kind of shock. Maybe some "compatible" one off a bigger bike, maybe an ohlins/penske/fox/whatever if you're more into "correct" parts.
Frame sliders (generally a good idea since radiators and gas tanks are expensive and sliders are cheap)
TPS adjustment, throttle body sync, fuel filter clean/replace, valve check/adjustment every 15k, compression check, new spark plugs etc. are all common maintenance items.
1g guys REALLY should do the mosfet rectifier. The stock setup is a good way to roast your cdi box or just get stranded somewhere
sv1000 guys REALLY should check your flywheel magnets. it's like the plague... everyone who has opened that cover has found loosey goosey magnets, or chunks of magnet in weird parts of their motor. Good way to cost yourself a thousand bucks by avoiding a $10 and 1hr check.
Green connector of death... look it up.
clean the front cylinder drain hole so you dont end up with an sv325
Anyway, i'm sure i missed something, and someone in the comments will call me a dumbass for something. So I expect that there will be good ideas in the discussion below as well.