I bought a 2003 Moto Guzzi California last year and had all kinds of issues going from idle to 'on throttle'. The engine would spit and jump and when I was just teasing the throttle on the highway it would lurch back and forth.
A little bit of research told me this was due to the bushings and seals on the throttle bodies wearing out and allowing air to suck past the housing, messing with the throttle position action and sending the vacuum units all over the map.
The parts required to put everything back in order could fit in a tablespoon, 4 bushings and 4 seals. I found a fellow that had completed the task on a similar bike and followed most of his advice. I'll attach the .Pdf file for anyone wishing to have a better look.
The Coles Notes of this whole process go like this:
- Didn't require any heat to remove the fixing screws top and bottom.
- Take off the intake manifold and the rubber housing at one time - much easier to manage.
- Mark the throttle position sensor position on the body for easy refit.
- Do grind off the ends of the 2 screws fixing the butterfly to the shaft. I used my drill press (for stability) and a small Dremel grinding wheel and took off only the first few thou.
- Note the way the seals should go back on. Chevrons to the outside. Not chevrons in like the last guy did to mine. Probably counted for part of the issues with sucking air.
- Bushings come out exactly as the other fellow suggests, being careful not to put too much pressure on the extraction process. They are split bushings so they will slide out nicely with a bit of pounding.(just kidding, go lightly here!)
- Re-assembly is straight forward if a)you remember where everything goes and b)nothing has dropped onto the floor where it disappears into the abyss with all the other bits.
There are a couple of good sources for the parts and don't let eBay trick you into thinking you need to spend $15 each plus crazy shipping costs. MY ChatGPT research assistant found these contacts:
The classic Moto Guzzi OEM part for throttle body shaft seals on many models is part number 25614997 or similar throttle body seal SKU (commonly referred to online under that number). This is confirmed by parts listings ? e.g., a Throttle Body Shaft Seal 25614997 available from aftermarket Moto Guzzi parts sellers.
Specialist powersports parts sites list 2003 Moto Guzzi California EV gaskets & seals including throttle-related seals ? you can contact them to request the OEM part number specifics.
https://www.wheelerpowersportsparts.com/oemcatalogs/c/moto_guzzi_motorcycle_street_2003_california_ev/aftermarket_street-engine-gaskets_seals?utm_source=chatgpt.comBushings were $4 each this time.
So, all things considered, a fairly easy fix for a real frustrating issue. The most frustrating of all though was trying to wade through all the crap being offered by eBay and other sellers. "Probably Will Fit" as a response really doesn't do it for me.
The takeaway from all this is to give your favourite AI program a try when looking for this kind of stuff. Model numbers, part numbers and other relevant details can narrow your search and produce some amazing results.
