Modern Vespa

Modern Vespa Howdy!!! I read some old posts about cutting a little on the gt 200 airbox for more vroom, vroom?? Has anyone done this recently, does it make much of a difference?? Curious Omer wants to know!!!

No it makes no difference to performance but it makes a lot more noise on the induction that could drive you insane on a long run! You can make mods but generally it's not worth it unless you want to invest in some other add ons too such as a sports exhaust, new free flowing air filter, rejetting the carb (which you would be well advised to do) maybe a new irridium spark plug etc etc. Even then most of the gains are just noise and imagined improvements. Dynoes don't lie and I've never yet seen any meaningful performance improvements from doing stuff like that. On the GTS250 got an extra 0.75hp out of the motor. It made zilch improvement to performance.

Go and buy a GTS.

Job done.

Next.

Bill x

Not a responsive or helpful answer. I think Stromrider pretty much nailed it; it's not going to do much as a standalone mod. If you are looking for better acceleration and/or top speed on a stock GT200, I'd suggest focusing your energy on the variator. There are a host of aftermarket products that will yield noticeable gains on a stock system. For example, I went with 10g Dr. Pulley slider weights and gained a few mph on the top end as well as slightly better acceleration. There are full-on variator kits, such as the Malossi Multivar and the J.Costa (which seems to yield the most gains -- look up Mike Holland's threads on it) but they can get pricy.

Of course it's helpful and responsive.

Making small changes to a GT200 will achieve nothing and spending a lot of money in it will probably achieve a little more, but not much.

So if you want to get more performance buy a GTS as it's already done for you.

Bill x

Paul Melici at PM Tuning dyno tested my original airbox mod, and found it made a one-third horsepower improvement over the whole rev range. Not bad for a simple backyard mechanic pocket-knife mod. But there have been many variants on my mod since then.

The mod gives you about the same performance gain as a Malossi red filter, but without the induction noise.

I first did this mod on a GTS250. Don't know how it will work on a carbed 200. But up-jetting definitely helps a GT200 performance. Increase your main jet by bout 5-10%.

But if you really want more performance you must fit a Malossi V4 cylinder and head. That will get you almost equal to a GTS300. All the other mods are just the icing on top.

Mike

the neat thing about cutting up your airbox is that if you cut too much, you get to buy another one.

I was concerned about performance at altitude, so I got very enthusiastic and drilled four 1 inch holes in the outside then stuck some plugs in that could be removed as needed by pulling to the side of the road and popping them out. Removing one did whatever I imagined it did, and more than that made the bike fall flat on it's face. Unless you can see your air fuel ratio in real time, you're usually imagining any changes you perceive.

When Malossi offers an airbox modification in one of their kits, it's a plug that's about 14mm in diameter. That's not a lot, so you don't need to hack away massive amounts of plastic to get much gains.

If you must

But if you really want more performance you must fit a Malossi V4 cylinder and head. That will get you almost equal to a GTS300. All the other mods are just the icing on top.

Or just buy a GTS 300.

What am I missing ?

Bill x

People put new bathrooms in old houses. They build conservatories on old houses.

Why don't they just buy a new house or are we missing something.

Well they do but it does make your house go any faster does it ?

It's performance were looking at here not scatter cushions.

Actually I think that you may just have stumbled into something that I didn't realise before.

Improving something actually makes you mildly more interesting at a dinner party or a coffee shop than someone who buys a bigger or better product.

There's more to talk about, more details to rake over and more interest in you which there may have not been before.

I've bought a GTS..........OK then. Fades to gray.

I need a bigger house so shall I make this one bigger or buy a bigger one ?

Or if you like that metaphor do what I did and buy two "houses".

Bill x

I'm sure the list is quite extensive, but what comes to mind first in this instance is knowledge about the subject matter. First hand experience is a close second. A GT 200 with a Malossi setup will outperform a stock GTS 300. The top speed difference is about 7-10 mph.

I don't doubt it but who buys small displacement scooter to go fast ?

Just buy a bigger, faster scooter either that or a motorcycle.

I have this, I want this to go faster than that so I'll tune this to be like that.

Or I'll just buy that.

It's like trying to add performance parts to my Toyota Aygo. It's pointless especially when there's a Camry available.

Let me explain that there is no subtext or a desire to subvert in any way.

I just don't something that I don't understand.

Bill x

So you say the GT 200+ will do 91-94mph? That it has at least 20% 30% more power than the GTS300?

I was thinking that.

Well, more like chose not to believe it more like.

Actually why doesn't someone who makes that claim prove it ?

You set it up and I'll ride the GTS.

Bill x