Author Topic: K75 starts but only idles to about 750 RPM (Solved)  (Read 2969 times)

Offline frankenduck

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K75 starts but only idles to about 750 RPM (Solved)
« on: May 02, 2025, 09:06:13 PM »
Reviving a K75RT that's been sitting for something like 15 years. Did all of the usual rehab stuff and was expecting to run right first time. Once the fuel system filled up it did start the first time but would only idle at 750 with the charge light still on and any gas or choke would kill it.

When I was swapping in a known good L-Jetronic I saw what I'd forgotten to replace - the crankcase breather hose. I have several on hand so I swapped in a new one and it fired right up and runs well.

I'm just posting this for someone who gets these symptoms and Googles for a solution.

More here:
https://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/ccb/ccb.htm

Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
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Offline The Mighty Gryphon

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Re: K75 starts but only idles to about 750 RPM (Solved)
« Reply #1 on: May 03, 2025, 01:50:47 AM »
The infamous "Z" tube. 
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

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