Bonneville America Forums Forums Technical Forums General Tech Triumph America oil gear question

Hi Everyone- Anybody replace their nylon oil gears with metal gears? And if you did where did you get them? Thanks for your reply’s!

Why would that be necessary?

Hi - because anything plastic in any engine is IMO the most stupid thing you can do. Wears out sooner than metal and melts at a lot lower temps than metal. If I ever have to pull my clutch cover I like to change mine to metal I know some folks have. Thanks Bob

Thanks...I understand your thinking..it's just that I've never heard of this being a problem on our bikes.

A few guys have had theirs melt because they let their bikes idle too long and the plastic gears melted then oil stopped flowing then Ruined their engines- IMO mainly because of a plastic oil gear. A big Nono in aviation engines to have any plastic parts inside hot oil in engines. Harley used to use plastic in some of their engines and of course they failed. Making a lot of unhappy people. If I was in stop and go traffic a lot like in LA I’d would have switched mine asap! Or not have bought my bike- I’ve been at train RR crossings on my bike and shut my bike down while waiting for the train to clear— Thanks Bob

Thanks that's interesting.
I was aware of the issue on early Kawasaki VN1500s... But hadn't heard of this issue in TBAs...which I'd always understood to be pretty reliable and robust mechanically....and of course I think we have two oil pumps in our engines don't we?
Or maybe that's just double trouble?

You should never idle an air cooled engine that long. If they melted the oil gears then they did other damage too. Metal gears would also wear the aluminum housing much faster than the plastic will.

Also, I heard of one guy’s engine plastic oil gear got brittle and cracked from always being in that hot oil all the time and failed. Thanks

I've been in this site these last ten years... I've heard probably most of the problems that these bikes but I have to say that I have never heard of anyone's oil pumps failing.
If it's not broke,don't fix it

If I end up keeping my bike and I’m in there doing clutch work I think I change mine to the metal gears. You used to be able to find the metal replacement ones , but was looking to see if they were available on line somewhere and haven’t been able to find them so it’s probably a none issue for now.

I occasionally have mechanical worries about all my bikes and their vulnerabilities....they're usually unfounded in my case.
With TBA/SMs I'd worry more about starter idler gear issues on pre 2006/7 models.
That ought to be enough to keep us all awake at night.

Super good point fortunately I have a o6 America but I learned to not give it any throttle when starting cause of that boss starter issue.!! Man now I’m working on getting corrected preload setting on my forks- what a headache!!

Yes, the factory suspension on these bikes is not of the finest quality.
Good luck.