Suzuki TS185 Jetting Issue

A reader’s 1975 Suzuki TS185 runs nice, but starts to have problems when it approaches full throttle.

Reader Contribution by Steve Foley
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by Keith Fellenstein

Editor’s note: If you’re having trouble with that old Suzuki, BSA or BMW, Keith Fellenstein is your guy. From motorcycle tuning tips to detailed motorcycle engine repair, he can draw from a wealth of experience to help guide you to success. Send questions to: Keith’s Garage, Motorcycle Classics, 1503 SW 42nd St., Topeka, KS 66609, or send an email with “Keith’s Garage” as the subject.

Q: A year ago I picked up a nice 1975 Suzuki TS185 and have been restoring and riding it, reminding me of my youth. I owned a 1972 and 1974 185 along with many other RM and TS models when they were new models.

My problem is the bike runs very nice, but from maybe 5/8 to full throttle it seems to blubber. My thinking was that it must have the wrong main jet, but I checked and it has the correct No. 125 jet. I did find and repair a couple small exhaust pipe cracks.

I have moved the needle clip up and down but now I am stumped. I have the carb somewhat apart and soaking in cleaner now and a new No. 125 jet has arrived in the mail. Do you have any suggestions? I am having a great time tinkering with the bike, but this is making me pull my hair out. Thanks.

—  Steve Foley/via email

A: Steve, you may have the correct numbered jet installed, but do you know if it is in original condition? Back in the day of expensive, hard-to-find parts and bad information, many a main jet was drilled out thinking that more gas means go faster. Try your replacement jet and see if that makes a difference, if not try a No. 120 or No. 115 and see if that changes things. Don’t go too lean too fast, that leads to piston seizure.

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