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n00b extraordinaire
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Discussion Starter · #1 · (Edited)
Hey guys,
So I just bought my first street-bike recently (very excited). I am trying to use it as a daily commuter for ~15mi a day to/from work and stuff.

Anyway, I have some super noobish questions. I have a decent mechanical background (I like to build cars, mostly) so I am not a total noob - just to bikes.

Here is what I bought for around 1K - a 1984 Suzuki GN 250 in pretty good shape.
















Tore the head off and cleaned a ton of gunk from the inside of the carb, and it runs pretty well now - starts right up and everything.



Anyway - I have some kind of basic questions;

Brakes - I hate drum brakes of all varieties - and the ones on this thing are shot to hell. Back brake barely works, and the front one is not very strong and is very sensitive at low speeds.
What can be done to fix this? I can't seem to find a good guide on overhauling a brake drum on a motorcycle.

I would reallllly love to do a disc brake conversion, but i don't know what to do about wheels. It seems like the drum is integral to the design of the ones I have, and a disc retrofit would need a wheel at the least. How do you pick forks for these things - meaning, what should I look for when picking out used forks on ebay for example. Looking at things like this;
http://www.ebay.com/itm/1981-81-Suz...Parts_Accessories&hash=item232bfa46b7&vxp=mtr

Suspension - Front forks are absolutely shot (bottom out on even mild braking). I guess this falls under the question of replace or rebuild. Rears look like there are tons of replacements for, so I am not concerned.

Tires - Ditto, but the ones on the bike are ~18 years old which scares me (degraded compound is unpredictable). Obviously i don't want to buy useless sets of tires, so I guess I need to wait until I know what wheels I am sticking with in the long-term.



Lighting - Planning on lighting this thing up like a christmas tree because I am deathly afraid of being rear ended by all the terrible drivers (been rear ended twice AND had someone head-on collide me while I was going through a green light - and I even came to a complete stop). Writing that makes me reconsider getting a bike - because that was my previous commuter 0_o

To hopefully prevent that - hyperlites to supplement the tails, some hyperlites for the turn signals (mounted under the seat, on the frame), and some equally bright front turn signals. I want my intentions to be absolutely clear. And not get hammered up the rear.
http://www.hyperlites.com/


What do you guys think I should do for the headlight? I need actual light output for when I do need to drive after dark - was thinking of just using these (I don't know if i have the energy + time to retrofit a proper projector into a housing, though one of those one-off CNC ones would be SICK).
http://www.ebay.com/itm/Photon-Twin...Parts_Accessories&hash=item53f4f908d4&vxp=mtr

How do I wire up turn signals? The bike doesn't have any currently. I was going to order a handle bar mount but I don't know how to wire it to the flasher, and the flasher to the actual signals. But there are only 2 pins on the flasher unit, which confuses me.
Handle bar unit -- http://www.ebay.com/itm/Motorcycle-...Parts_Accessories&hash=item3a8300c168&vxp=mtr

What do you guys think? Basically want to build a nice commuter that is way cooler than a mid 80's looking Ninja 250 :p
Deff going to push it more towards the streeghtfighter/cafe-ish look but I want to get it mechanically sound before doing so.

Need some nice bars too, but the riding position is actually pretty comfy.
 

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30,379 Posts
Congrats on the new bike and welcome to CF. First things first, get new tires. 18 year old tires are retarded dangerous.

Second, consider how long you plan to keep the bike. Being a 30 year old 250, I would guess that you are going to get bored with the tired ~20hp that bike has. If you just want to get the hang of riding, then focus on the safety times and making it run and ride good and save your money for a bigger bike. Add signals and lighting and check the front fork fluid, sounds like it might be really low.

The headlight you listed looks like a Dominator ripoff that has been overpriced. Check out Moto Madness, he is a site sponsor and has the same headlight for cheaper https://www.moto-madness.com/headli...0.html?zenid=f370464fe720511fda03aa9b9e140a24
 

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Bewbie
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435 Posts
You could probably find same size forks, wheel, brake from another small bike with a disc brake...... the right soze would just slide into the triple clamps...maybe a kz400, not sure of the dimensions but could be a match. My kz has the stock disc and caliper with braided lines and a ninja 250 master cylinder...I can damn near stand the bike on it's nose...
That route might be cheaper/easier if they measure up than possible having to press in a new stem if you get the whole front end from another bike.

Great looking bike by the way! Congrats
 

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Noobie
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2,644 Posts
welcome and congrats for the bike
that's a clean looking bike, even thought it's almost 30years'old

brakes: there's a disc brake version of that bike, would be easier to convert if you could find forks and front wheel from that version


suspension: seems there some oil leak on the right fork?

turn signal: if the cable is still available try find it, according to wiring diagram some version seems using 2pins relay.
here some wiring diagram for GN250:
http://s675.photobucket.com/albums/vv118/hmmmnz2/suzuki/?action=view&current=gn250e01.jpg
http://s675.photobucket.com/albums/vv118/hmmmnz2/suzuki/?action=view&current=gn250e28.jpg
http://s675.photobucket.com/albums/vv118/hmmmnz2/suzuki/?action=view&current=gn250e22.jpg
http://s675.photobucket.com/albums/vv118/hmmmnz2/suzuki/?action=view&current=gn250e26.png
http://s675.photobucket.com/albums/vv118/hmmmnz2/suzuki/?action=view&current=GN250colour.jpg
 

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740 Posts
First off welcome aboard and you did yourself a favor by starting out with a bike like that. So many people like to think 600 supersports are "starter" bikes and are in the hospital weeks later.

For the drum...while anything is possible, I wouldn't say it's reasonable to convert to disc. For a bike that small/slow it's not needed. As for "overhauling" the drum, yank the rear wheel and the outer cover just pulls out. Just two shoes and some springs. Often on older bikes the friction material breaks off the actual shoe and floats around the drum and on something that old has probably turned to dust. New shoes should take care of the problem. I've never really had complaints with drums on any bikes I've owned, they work just fine. New shoes will take time to break in, when you first install they will seem wooden. Just ride the brakes for a few miles and the power will get a lot better. If the drum has lots of deposits/crap built up on it, use brake parts cleaner and steel wool to clean it up.


See if the fork caps on your bike unscrew. While I kind of doubt your bike has it, a lot of 80's era stuff had schraeder valves on the forks to add air to adjust the stiffness. If they had 0 psi they were ultra soft, usually 3-5psi was normal. If not, then the forks need to be rebuilt. If that's not something you've ever done, I would consider finding someone to help you or letting a shop do it.


Turn signals are a very simple circuit. It's a lightbulb, switch, and flasher relay. When the switch is on (to one side of the other), current is supplied first to the relay (in one pin, out the other, doesn't matter which), then to the bulb, then to the other bulb, then to ground.

LED signals will not work with a regular flasher relay, they draw too little current. Usually stock relays are looking for 40-50w of load, or 2x 23w blinkers.
 

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Watch the world burn
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1,046 Posts
If you're riding on 18 year old tires, I bet your brake pads are much older. There have been test done and with the new materials brake pads are made out of there is almost no difference in stopping power between drum and disc. Since I doubt you're taking it to the track, I doubt heat will be an issue either. I agree with replacing the pads and flushing any fluid lines to see how you like them before investing in a swap.

As far as lights...unless you put on a strobing pinwheel about helmet high, I doubt it'd matter as far as cagers go. Bright jacket and helmet would probably do more.
 

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n00b extraordinaire
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18 Posts
Discussion Starter · #8 ·
Thanks for the help guys - sorry for the slow response, I am moving houses which always sucks a fat one.

Congrats on the new bike and welcome to CF. First things first, get new tires. 18 year old tires are retarded dangerous.

Second, consider how long you plan to keep the bike. Being a 30 year old 250, I would guess that you are going to get bored with the tired ~20hp that bike has. If you just want to get the hang of riding, then focus on the safety times and making it run and ride good and save your money for a bigger bike. Add signals and lighting and check the front fork fluid, sounds like it might be really low.

The headlight you listed looks like a Dominator ripoff that has been overpriced. Check out Moto Madness, he is a site sponsor and has the same headlight for cheaper https://www.moto-madness.com/headli...0.html?zenid=f370464fe720511fda03aa9b9e140a24
Thanks for the advice - I did see the one on moto madness but I was going to try to grab one that just comes with an HID kit. I was going to paint the chrome ring anyway so I might just grab the one from moto-madness and add in an HID kit.

The tires really are no good - I think I will just order a set off now and ride it as-is for a while just to be safe.

I really dont know how long I will keep it - at least through the winter though (I DO have a car, but I am rebuilding it currently). I already got bored with the speed, but thats kind of what I want. I see way too many downed bikers up here, and what I really want is to just get more confident on the bike before upsizing, plus my car is fast as shit and I dont really feel the desire for a fast bike right now.


You could probably find same size forks, wheel, brake from another small bike with a disc brake...... the right soze would just slide into the triple clamps...maybe a kz400, not sure of the dimensions but could be a match. My kz has the stock disc and caliper with braided lines and a ninja 250 master cylinder...I can damn near stand the bike on it's nose...
That route might be cheaper/easier if they measure up than possible having to press in a new stem if you get the whole front end from another bike.

Great looking bike by the way! Congrats
Thanks! The front sits way too high and chopper-ish right now but I guess I can fix that at a later date if/when I mod new forks in. There are a decent amount of options for a front end I guess, I just need keep my eyes open for a hot deal.

Turn signal wiring seems pretty straight forward (thanks for the explanation, was a big help actually).


My plan as of now is to;
1. Either rebuild or just top-off the fluid in the forks
2. Rebuild brakes somehow
3. New tires
4. Signals, proper brake lights, headlights

Next problem -- The rear brake light also only actuates with the rear brake - I cant figure out where a switch would be on the front.
The rear switch is actuated when you push on the pedal, by pulling a switch+spring combo outwards. No switch is visible on the front though.

I am also trying to figure out why the throttle likes to "balloon", meaning it idles at ~900rpm just fine but it will just get stuck at ~2000 rpm until I blip the throttle and slam the throttlebody closed. The cable is not sticking so I assume it was something I fucked up when I cleaned the carb out?

I also destroyed the gas-cap when it got stuck and refused to open (literally had to pry it upwards to break the plastic retainer ring). Thing was 30yrs old so I cant be too mad I guess :/

Vintage shit is fun :rock: :confused:
 

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Damm nice starter bike mate werebouts in VT are ya ?iim nextdoor in NH ;)
 

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n00b extraordinaire
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Discussion Starter · #12 ·
Damm nice starter bike mate werebouts in VT are ya ?iim nextdoor in NH ;)
Never been to vermont :drinks:

Very exploitable loophole in their DMV system that lets you register motorcycles over ~20yrs old, or under 250 CC (or both), WITHOUT being a state resident!

This one is essentially a "barn find", and hasnt been titled in many moons. Neither Colorado nor Florida (my state of residence) would title the bike so I went through VT.


Scoping tires out right now - I dont have any riding gear of my own so I am investing in a helmet and riding jacket, and stealing my friends old riding pants that are pretty clean. Tires will be next, brakes will be after that (i over exaggerate how bad the front one is, it stops just fine but is grabby at slow speeds). Lights are cheap and I already ordered the rear signals, just need a bar mounted switch to go with it, and ordering these horns on Monday as well;

http://www.ebay.com/itm/2-x-Black-M...Parts_Accessories&hash=item4857e05c84&vxp=mtr


Excited as hell but I cant even ride the damn thing because I broke the gas cap :(

MSF course is next weekend, which I cant wait for...
 

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Make sure you wear sturdy, well fitting over the ankle boots while riding also. It's fairly easy to roll an ankle if you step in a pothole at a stoplight, or the bike tips too much and "gets away from you" maneuvering at low speeds or something. Sneakers or loose, slip on boots will instantly fly off if you take a tumble.
 
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