Author Topic: T3 throttle question  (Read 1872 times)

Online Anomaly

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T3 throttle question
« on: April 02, 2026, 01:28:32 PM »
I finally found the source of my sticky throttle problem (wouldn't snap back to zero when released)-- it wasn't a cable issue, but rather an accumulation of dirt/sludge between the "throttle tube" and the handlebar surface. To access the problem area I had to split open the two halves of the switchgear to liberate the throttle tube. Never having done this before, I initially removed the two thumb screws (see photo), but those are not the two screws holding the halves together...Doh! I found the correct screws, split the halves, removed the tube, cleaned everything and heeded Richardson's (Guzzioligy) advice to back off the tiny set screw before trying to screw the halves back together on reassembly. But my question is what is the purpose of the two thumb screws and how should they be adjusted (given that I had completely removed them)?

A second less pressing question is is there a replacement for the entire throttle assembly? Richardson says the original is no longer available. Stein Dinse has something that seems to be a replacement. My plastic throttle tube has clearly seen better days but I'm not sure I'm ready to replace everything, but curious what options exist.


1981 T3 California, 1983 Piaggio Apecar P2
Sold: 98 BMW F650, 2012 v7 Classic

Offline turboguzzi

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Re: T3 throttle question
« Reply #1 on: April 02, 2026, 01:41:25 PM »
the thumb adjuster nearer to the orange button sets the max limit to throttle opening so that you dont stretch/break the cables if you are going WOT.... :)

the adjuster central under the throttle ADDS friction, in case you will miss the dirt you had there.

Common mod is the Tomasseli Daytona 2C throttle. I have it on my LM III that has 36 carbs, so needs quicker opening, not sure it's of any value on a T3.

Also adds a new proble of having to modify the switch block or go for a different one altogether because of missing room on the bar problems.

Pretty happy with the stock one in my SP

Online Anomaly

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Re: T3 throttle question
« Reply #2 on: April 02, 2026, 02:36:43 PM »
Thanks Turbo!! I'll take it for a test ride tomorrow and apply what you indicated if needed after.

Not sure I would want to go the  Tomasseli Daytona 2C throttle route given the new complications. I do have PHF36s though...
1981 T3 California, 1983 Piaggio Apecar P2
Sold: 98 BMW F650, 2012 v7 Classic

Online moto

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Re: T3 throttle question
« Reply #3 on: April 02, 2026, 02:45:59 PM »
The second, friction thumbscrew is there to offset the pull of the strong throttle return springs. It works well for that purpose, properly adjusted.
850 T-3
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2023 Royal Enfield Classic 350
Italjet Buccaneer 250 (ex-SSR) -- now sold
credit for 2500+ postings lost in the database meltdown of Feb 9, 2020

Online Anomaly

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Re: T3 throttle question
« Reply #4 on: April 02, 2026, 02:50:51 PM »
The second, friction thumbscrew is there to offset the pull of the strong throttle return springs. It works well for that purpose, properly adjusted.

"properly adjusted" there's the rub....  :undecided:
1981 T3 California, 1983 Piaggio Apecar P2
Sold: 98 BMW F650, 2012 v7 Classic

Online moto

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Re: T3 throttle question
« Reply #5 on: April 02, 2026, 04:25:32 PM »
"properly adjusted" there's the rub....  :undecided:

Not hard at all. Just experiment. Make sure that it will allow the throttle to still close the throttle when you take your hand off.
« Last Edit: April 02, 2026, 05:47:18 PM by moto »
850 T-3
Griso 1100 corretto
2023 Royal Enfield Classic 350
Italjet Buccaneer 250 (ex-SSR) -- now sold
credit for 2500+ postings lost in the database meltdown of Feb 9, 2020

 

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