Sa50 with big bore, carb question.

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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Mrhyde20027
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Sa50 with big bore, carb question.

Post by Mrhyde20027 »

I put a big bore kit on my sa50(af18e) and I'm not sure if I can just order a new carb that will fit or if it's easier/better to rejet. I have been trying to find what will work but I do not understand enough and do not want to order something wrong. Is there a carb I can order or which and what kind of jet do I need if not. Thanks
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Re: Sa50 with big bore, carb question.

Post by MrJumps »

What bbk did you order and on some bbk you can just rejet but it all matters on bbk size.
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Re: Sa50 with big bore, carb question.

Post by Mrhyde20027 »

48mm 80cc
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tazland001
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Re: Sa50 with big bore, carb question.

Post by tazland001 »

Start off with 100-105 main jet and free flow filter if you want to run the stock carb. Are you running a gear ratio upgrade?

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Re: Sa50 with big bore, carb question.

Post by MrJumps »

You could drill out the idle jet to match the bore idle, but if you dont run the stock airbox and filter you will never get it to run right.
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Re: Sa50 with big bore, carb question.

Post by Mrhyde20027 »

I have not upgraded gears. Ty for responses. One of my problems is I was trying to find a new carb to mount on the 35mm bolt connection. Didn't realize could just replace intake. Anymore information I would be glad to read, thank you
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tazland001
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Re: Sa50 with big bore, carb question.

Post by tazland001 »

Guys come on. You can run the stock carb with the stock pilot and up-sized main jet. It runs fine. If your running a 47-48mm a good main jet is 100-102. A 50mm is a 105 main. You can either mod the stock air box with 3 one inch holes in the air filter box cover and add 1 inch uni breather filter plugs. You don't have to use the uni plugs if you don't want to. The air will still pass thru the filter. Or you can use a uni free flow sponge filter. Either way it runs great. Plug chops are the proof.

Also you want to run gears before you do a pipe or carb. It is silly to add a BBK then put a muffler or carb without gears. Once again gears are 70% of the upgrade. You cannot ignore gear ratio upgrades. Gears are the biggest bang you can get for your buck.

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Re: Sa50 with big bore, carb question.

Post by burnt_toast »

Taz, so what is a good main jet size with stock unmodded airbox and 47mm?

I'm in the this same boat with my zx50, has malossi 47mm bore kit and tecnigas exhaust. Going to be for resale so I pilfered its 19mm dellorto and switched to stock from intake up, beside CF reed. got rollers sorted, shifting well. So far tried a 90main, and feels good at WOT but hesitates at mid throttle when letting off..

thank you graphite9 for the jet kit btw, its perfect for this!
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Re: Sa50 with big bore, carb question.

Post by Wheelman-111 »

Greetings:

Stock carb, airbox and stock-pipe F9 likes a 90 main, chokes on a 92. If I had a Technigas pipe I'd try the 92.
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Re: Sa50 with big bore, carb question.

Post by burnt_toast »

thanks wheels. gave 92 a shot, and still choppy in midrange w/ stock box. richened clip and same story.

however at any setting, with box removed and just open carb, runs like a champ! thru all throttle pos. like great pull all around and the open filter actually complements sound of the tecnigas pipe pretty well :twisted: likely on lean side, but it was just a few test runs.

SO decided I'm gonna ditch stock box, and installed a open UNI filter w/ a custom splash and shock guard. upjetted to 96 (-1clip, rich)since that's max I have on hand. have yet to try with all this crazy rain we've been having here in TX, but looking forward to it! 8)
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Re: Sa50 with big bore, carb question.

Post by burnt_toast »

(realize im kinda hijacking this thread, but seems like good info to go in here :nerd:)

SO tried the 96main, +1clip rich, and open UNI filter last night. Ran OKAY, not nearly as yank happy as with the 90 or 92main, and def felt on the rich side. Makes me think going any bigger is not going to do me any good. trying to set up for a 50mi scooter ride in 4days.. will try to proper plug chop if time permits, otherwise might wing it and go by feel

I wonder how much elevation plays a role in A/F adjustment, i'm at 650' above sea level for reference. howabout you guys up north?
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tazland001
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Re: Sa50 with big bore, carb question.

Post by tazland001 »

That does sound a bit lean on the main. I would just go as high as you can go without any sponge on the top end. Make sure that pod filter is not restricting air flow in. How did the 96 main run without the pod filter?

I would deff slap a new plug in and do plug chops just for peace of mind.


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Re: Sa50 with big bore, carb question.

Post by burnt_toast »

old post, but wanted to update: went with a custom filed jet to about ~102 size, with the open UNI. this combo has worked wonders, with no seize or issues with WOT for long stretches
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Re: Sa50 with big bore, carb question.

Post by Meloshameless »

I built 2 elites, corsa/yasuni/intake/carb. The other corsa/arrow/intake/carb. Kept stock gears on both and did 55mph on one and 65-70 on the other and loved the wheelies. Point is i dont think you NEED gears. Thats a personal choice depending on how you like to ride.
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burnt_toast
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Re: Sa50 with big bore, carb question.

Post by burnt_toast »

Meloshameless wrote:I built 2 elites, corsa/yasuni/intake/carb. The other corsa/arrow/intake/carb. Kept stock gears on both and did 55mph on one and 65-70 on the other and loved the wheelies. Point is i dont think you NEED gears. Thats a personal choice depending on how you like to ride.
agreed. considering going this route on a future build, sounds like such a rev happy setup :smile:

how's the holeshot takeoff from a deadstop? bet its gotta be a pretty hard punch, like is it even controllable or just instant wheelie??

one concern i do recall hawaii guys mentioning was gears running too hot at such high revs even with 9:1. did you do anything to address this or have any gear heat issues? full synth 10w40 might help some. is your riding mostly stop and go or have you been able to go long distances wot at these revs?
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