suzuki t500 74 running prob

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merlin1
Still in the Driveway
Posts: 4
Joined: Sat Jan 02, 2021 5:17 pm
Country: United Kingdom
Suzuki 2-Strokes: 1974 t500

suzuki t500 74 running prob

Post by merlin1 »

hi everyone i have a 74 T500 which i have purchased completly restored , it has titan pipes on it , starts no problem , but mid throttle holds back sounds like its oiling up , full throttle goes like a rocket revs nice , checked carbs all nice and clean with standard pilot jet , main jet has a 102.5 which the main man at titan has told me with a standard air box be ok , i have checked all ignition and timing settings , which are spot on , and engine idles good on centre needle clip , what am i missing would love to get it on the road this summer thanks in advance happy easter cheers chris cornwall.
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ConnerVT
Novice racer
Posts: 963
Joined: Wed Jan 18, 2012 8:01 pm
Country: USA
Suzuki 2-Strokes: T500R (now), T500M (40 yrs ago)
Location: North of Albany, NY

Re: suzuki t500 74 running prob

Post by ConnerVT »

Ah, the joy of carb tuning.

Sounds as you may need to move the Jet Needle clip up or down. The needle is the major control for mid-throttle mixture.

Assuming the clip is in the 3rd slot (there are 5 slots on the needle), the question is do you move it up a notch (away from the pointy part) or down a notch. Moving it down will make the mixture at middle throttle richer (needle further out of the Needle Jet), moving it up will make it leaner.

It takes a little feel to tell which is needed, as it is hard to tell sometimes if it seems the motor is bogging down or jest not getting enough fuel. One tell is riding at mid throttle and feeling sluggish, roll back off the throttle just a hair.

If the engine picks up and starts to accelerate, you are probably rich and need to make it a bit leaner, and move up a notch.

If the power just drops off, you are lean, and move the clip down a notch, making the mixture more rich.
merlin1
Still in the Driveway
Posts: 4
Joined: Sat Jan 02, 2021 5:17 pm
Country: United Kingdom
Suzuki 2-Strokes: 1974 t500

Re: suzuki t500 74 running prob

Post by merlin1 »

Thanks I will give that a go cheers
Vintageman
Expert racer
Posts: 1483
Joined: Tue May 18, 2010 5:38 pm
Country: USA
Suzuki 2-Strokes: Suz, Yam, Honda, Kaw.
Location: New Hampshire

Re: suzuki t500 74 running prob

Post by Vintageman »

If that doesn't work. I would look inside needle jet with good light and eyes. I suspect being original it is pitted a bit where it meters with the jet needle. Should be shinny, smooth and precise.
Current Bikes
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