Suzuki 125 4 stroke questions

Hi guys!

Mentioned in another thread, I picked up a '96 Suzuki GN125E, a little street bike. From what I can figure out the engine, 125 4 stroke, is the same that Suzi has used from the early 80's DR and DRZ, also Kawie KLX 125.

I need this bike for street use on steep mountain roads at 3,500-4,000 ft elev. Need maximum torque and strong lower to upper midrange power. I'd like to open up the exhaust but don't want a lot of noise, prefer more mellow than rappy. Any suggestions for an inexpensive spark arrestor slip-on that's fairly quiet?

Can't seem to find much on cam specs, most places just say 'Race grind', gee, thanks for the detailed info. For max torque I'd want short duration - minimum overlap and fairly high lift, not a top end screamer. Suggestions?

Lots of carbs out there, seeing the VM-26, Kei Hin PE-26 & K/H round slide 26. I think stock is 22mm Mikuni. Wondering if I'd want a 26mm carb with only a cam and exhaust upgrade, or if that's not needed except on big bore kits?

Problem I'm having is building strong street performance & long term reliability at lower midrange rpm's instead of building all the power with the tach buried and parts flying.

Oh, and as usual, low budget. Open to suggestions, THANKS!

Happy biker here, got the new bike running! Didn't run when I got it but price was so right I took a gamble: good bet, not a whiff of smoke. Had to use a jumper wire to short the solenoid, haven't figured out the circuits yet, something there isn't right. Also the carb seems to want some attention, couldn't get over 6,000 out of it and kinda balky on the way up, but engine runs like a sewing machine.

Last note: realized this thing has a potato up the exhaust, a catalytic converter boo hiss. Latest model bike I've owned and not a joyful discovery, gotta do something about that....

Great job on getting it up and running!

On the other hand, that potato means there's a lot of potential there...

Good luck with it,


Thanks for the encouragement, Kirk! I'm really happy it's a goin' as I had no idea if the engine was trashed or what.

Now re-thinking things and may build it a little hotter than planned. Already have my low miles XL-100 rebuilt for a fun econo-cruiser plus trails and dirt with a 125 engine still to rebuild and install. May do a more cafe oriented build on the Suzuki for pavement pounding. Should be fun regardless. Thanks for the feedback..

By the way for any reading & searching info: '96 Suzuki GN125E is NOT a 22mm Mikuni stock: VM20 SS [pilot screw preset, 2 1/4 turns back, idle 1,700], 9.5:1 compression, CDI ignition, DR8EA or X24ESR-U plug gapped @ 0.6-0.8mm, timed 13* BTDC @ 1,700, 10W40 oil at 950ml filled to center of sight window level on center stand, about 12 HP, 5 speed, electric start only. Well, yeah, you could push it real fast and hop on, done that before haha!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now