Sprocket Suggestions for Boney Hare Scrambles

Just completed in a vintage hare scramble this weekend on my 1980 390WR after taking a 44 year hiatus. It was pretty boney compared to enduros that I recall in the early 80s. I had an 11 tooth sprocket in the front and a 53 tooth sprocket in the rear, whereby 1st gear still seemed too fast to navigate the rocks.

Although it was more than likely me than the bike, does anyone have different suggestions for the drive train to deal with boney conditions?

Any suggestions would be appreciated. Thanks.

11 is too small from a lifespan standpoing probably from other ways of analyzing things. Besides trials bikes or the ktm battery bike I doubt 10 or 11 are delivered on a stock new bike. If you are in first gear you will get tired fast. You asked for any suggestions. Use a higher gear. Is this a NETRA event you entered.

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Yes. It was the NETRA Indian River vintage hare scramble. It was pretty boney and I really struggled not to go too fast in first gear. I’ve got a 12 tooth front sprocket, but I figured it would only make it faster in first gear.

Seems to me higher gear so when on throttle it can be more open, maybe power pulse vs ground distance makes why it works better. I have lately gone battery dirt bike and the KTM one will go as slow as the rider wants.

I entered one of those events quite a while ago . The guys passing were well behaved at the begining but really aggressive passing toward the end.

I'm not familiar with the term "boney" but based on the rest of your comment it sounds like you were navigating a technical area of the coarse. If your riding level doesn't allow you to go fast enough without stalling then the obvious solution is to use a larger rear sprocket. Maybe a 56 tooth? Not being able to slow down in a technical area without constantly working the clutch will eventually roast the clutch. A rear sprocket is cheaper and easier to replace.

fran...k is right - an 11 tooth countershaft sprocket will quickly contribute to chain wear.

Your 11 / 53 sprocket combo translates to a 4.82 ratio. Since you are wanting to go 'slower', consider going to a larger rear sprocket as Crash suggests. Using a 12 tooth (minimum) countershaft sprocket with a 63 tooth rear sprocket will give you a 5.25 ratio - this would be higher than your current 11 / 53 setup.

Below is a sprocket ratio chart to help in choosing an optimum combo. Also, a 'Sprocket Calculator' that show percentages of speed and torque increase/decrease with differing combinations of countershaft and rear sprockets.

https://sprocketcalculator.com/

And lastly - a link to 'Sprocket Specialists' showing availability of rear sprockets sizes up to 74 teeth!

https://sprocketspecialists.com/product/rear-sprocket/

Since you have had a 44 year hiatus there are spongy hoops called moose or maybe a different similar spelling that the other guys may have in their tires. I asked one guy just a few days ago if he had them and he said oh this bike has tubliss in the rear but moose in the front is a must. I guess I could also add I worked a check with an isde level guy and he was adamant to use the moose from the tire maker. Or I guess the right sized one. Not sure if this matters for a front.

Thank you for the information and the link to sprocket specialists. I'll try going back to the 12 tooth in the front and a larger sprocket in the rear.