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81 xr 500 reeds? can i chuck them?

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my xr sucked a reed into my valve, but didnt wreck anything. im wondering why the bike has even got them, and can i just get a spacer and chuck the reeds and cage, or do i need them to run the bike?

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Back in the day, White Brothers used to make a reed replacement deal that kinda made a port transition to the valves. When the reed block is removed, I can't imagine it being helpful with flow characteristics since there's a big rectangular void left when the reed assembly is out.

But, I have heard of people removing them and running the bike like that.

Try it and see how it goes. Report back your results. I'd be interested in hearing how it runs.

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well im thinking i might just go to the local bike salvage yard and see if i cant find myself a new set of reeds for cheap... but ive heard that people have taken off the whole cage and the bike runs great, just with a little less power... kind of stupid to have reeds on a thumper though, dontcha think? :lol:

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Well, Hondas thinking back then was the reed assembly got rid of the cough and die syndrome that plagued big bore thumpers when you whacked the throttle open at low revs.. It actually worked but sucked top end power out of the engine.

Modern thumpers use pumper carbs to achieve the same end as Hondas reed did--without any horsepower loss--and usually a gain.

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could you use epoxy to fill in the void? (build your own intake track?

Hi zrxer---have a great thanksgiving and the rest of thumpertalk---------

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could you use epoxy to fill in the void? (build your own intake track?

Hi zrxer---have a great thanksgiving and the rest of thumpertalk---------

my thoughts also

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could you use epoxy to fill in the void? (build your own intake track?

Hi zrxer---have a great thanksgiving and the rest of thumpertalk---------

Hi bergman! (Or should we call you non-bergman now lol.) You do the same, man!

Hmmmm... Epoxy. That's something to think about.

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i havent gone yet but will be going to the salvage yard tonight. does anyone know if all the xr's from that period have the same reeds? im sure thay will have to have a few xr's there so shouldent be too hard to find them... just took another look at my carb, and noticed the cover on the top was broken....made of plastic :0 i wonder if thats why my bikes been running like junk? lol.... anyways, if i cant find a new set of reeds or a whole cage, epoxy sounds good. but will it ruin all the bottom end power if i take out the reeds?

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They only made that reed system for one year,if i recall. Iv'e read that it really messes with the jetting when removed. I would think the cam timming might be different for that year to take advantage of the reeds.

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The '81 and '82 XR500R were the only years and models to use the reeds. The XL500Rs never used them.

To my knowledge, the camshafts were all the same.

You know, if you wanted to get this far into your engine, you could scan ebay or your salvage yard for an entire '82 XL500R head and bolt on your bike.

In fact, all the '79-82 XR and XL500 heads wil bolt on to your bike. The only difference with the older heads ('79-'80 XR500 and '79-'81 XL500) is they didn't have automatic cam chain tensioners like your bike but I THINK the tensioners bolt up the same. You might want to check on that though. It's been a while since I messed with the early engines.

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im not a very big ebay fan.... but i went to the salvage yard and they had never even heard of reeds in a 4 stroke! :lol:

but after looking in a shop manual, they decided it would probably run with one reed missing, so i am just going to clean the carb and get it running for now until i sell it.

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