Honda Spree and Elite 50 Forums

So I just picked up a 1997 SA50P. It's mostly original and I love it.

It tops out at 30 so obviously I'm looking into de-restricting it, but before I buy the parts I need I was taking a look at it to see if it had been messed with already and I came across a weird problem. One of the slots in the air box cover was stuffed with a paper towel. I took it out, the more air the better, right? I took it for a spin to see if I gained anything by doing that and once it would get to about half throttle it would bog down and not go any faster. Didn't matter what speed I was at, only the throttle position. I put the paper towel back in and all was good. What the *? I'm guessing it would be a carb issue but how would only a little bit more air flow make it do that? I tried a mechanic friend and google and didn't find an answer so now I'm here. It's not a big deal as I can obviously just leave the slot blocked, but I'm really curious whats happening here and am hoping it doesn't affect the mods I am going to make here soon.

Here is a picture without the towel blocking it. Clearly someone drilled out the one slot, not sure if there is plastic there when stock or maybe just a smaller hole?
https://i.imgur.com/HzcD6np.jpg

And with it blocked.
https://i.imgur.com/vEu5nxw.jpg

Tape it up, use a proper filter, problem solved. Really wish people would stop treating scooters like they are high performance motorcycles, or trying these stupid hacks. It inevitably ruins the bikes and makes them run poor.

Theres two air intake holes in the airbox lid, one should be blocked off. Install a new filter and spark plug. Clean the carburetor and up-jet the main to #78. Drill the washer out of the exhaust and re-install with a new gasket ring. Remove the restrictive plate on the variator. Zip-tie the oil pump to full open......go 40mph.

That's so weird to me that the one slot needs to be blocked off. But yea thanks for the tips, that's what I plan on doing next week.

The reason it needs to be blocked off is because it was running too lean. Essentially that means there was too much air in the piston when it was igniting. It can cause your engine to run much hotter and possibly seize if ran too long when lean. The best option would just be to upjet to a #78 and that will fix your problem as quickly as possible. If you want even more performance you can do the variator back plate and then all of the other things but if you just want to get it running good and not worry about everything else then upjet to a #78.

Grizz wrote:it would bog down and not go any faster. Didn't matter what speed I was at, only the throttle position.

That's called lean bog. Don't do that.