Gearing on a Thunderace

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Scratcher
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Gearing on a Thunderace

Post by Scratcher »

I am impressed by the info in the workshop area
"Gearing on a Thunderace"
Original article submitted by Yeasshhh

But I may have made a mistake yesterday afternoon (under the influence of a 'sesh' with the few brave enough to call themselves my mates!)

I read the article and thought that sounds like the Dog's...... I'll go for a 16/48 tooth combination from the standard 17/46 and get a big acceleration boost and lose the bit of top end that I never get to use. Aren't I so fookin clever.

This morning, under the cloud of sobriety that affects us the morning after, I've re-read the article... and I've spotted something that is making my smug barsteward feeling wither....

"So, what does this mean? Starting at standard gearing, if you go up 2 teeth on the back then your acceleration should be 4.36067% faster, technically speaking... So, if your 0-60 is 3.5 seconds then this change in gearing should take it to 3.3471655 seconds. Or thereabouts.

Or, if your top end is 170 mph in standard gearing and you go up 1 tooth at the rear then it will drop to 166 mph. Go up 2 teeth, then it will drop to 162 mph.

Or, if you go to 16/48, your top speed will drop to 151mph, acceleration will be 10.86474 % greater and the side effects will be enormous! Acceleration will be 10% faster! "


Can someone please explain to an exceptionally thick (and we're not talking just girth) pentagenarian how he may have just fooked up... WHAT SIDE EFFECTS?
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Stig
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Post by Stig »

That article was a long time ago!!!

As far as I know.....
You'll be changing gear a lot more frequently for a start, depending on your style of riding and what you use the bike for then the ideal rev range may be totally thrown out. You may end up over reving at say motorway cruising speeds or you may get 3ft in first gear before you need to change up

Fuel economy may suffer too or the angle of the chain may wear the swing arm pivot area
AKA Bald headed b'stard
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Scratcher
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Post by Scratcher »

Thanks Stig & Nuggitt.
Think I may have over cooked it a bit, then.

I commute only a short distance (south of Mansfield to Clipstone) then there's the up-coming RTTW on 1st October... plus any trips to the MFN/Matlock etc.

I'll have to buy a stock 46T rear sprocket to try and calm the side effects down. But I'll wait until I see the full effects of the changes.
I've dropped the clanger, now I'm gonna have to live with the consequences or shell out more of my hard-earned!
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