Modern Vespa

There is a wealth of great information on this forum and I think I have found enough detail to try wrenching the malossi 70cc kit myself. What hasn't been discussed is how performance mods affect fuel efficiency. I bought my 07 lx 50 for gasoline savings first, and fun second, and i want to keep that order in tact. For my riding application, the bike's stock power is almost enough- so another 10 mph would be all i need. I am clocking around 75 miles per gallon and would be okay with a 10% or less drop off

so for all out there that have made the 70 cc upgrade, or any other upgrades for that matter- please share your personal experiences in efficiency changes so i may better decide if the power trade is worth it.

Thanks and Keep Scooting!!

With my ET4 150 I get better than 60 mpg.
And that's spirited riding too, If I was just commuting it would be better still.
Not knocking your scooter or choice or anything like that, I still have the Derbi Atlantis I started with.
Just saying maybe you'd be better off getting a bigger scoot, unless you like wrenching, then go for it.
BTW I am doing some mods to my 150 to make it perform better so it can be a battle to stop the insanity once you get going.
Mega.

I did Mike's mod and it not only did not improve performance, it actually appeared to have reduced it.

Done with performance modding, thank you very much.

Performance modifications are always a compromise. You always give something up, to get something when you make modifications.
If you approach it knowing that some quality of performance or behavior will be exchanged for another one then hopefully you wont be surprised or disappointed.

Unfortunately you dont always get what you expect and rarely know what youre giving up till you've done so.

For that reason I've personally come full circle to appreciate leaving my vehicles well enough alone performance-wise.

YMMV

In my own opinion, one's chances of success depend on both the realism of one's expectations and one's ability to approach the task with sufficient knowledge and understanding of how everything on the scooter works together as a system (not something you are born with; it's something you acquire through a major investment in personal research and experience... tempered with a healthy dose of skepticism).

Successfully modifying a scooter (or any other vehicle), is most decidedly NOT an exercise in bolting on assorted "performance parts" and expecting results equivalent to the accumulated claims for each device. In fact, without an intelligent systems approach, some things can work at cross-purposes and produce a net decrease in overall performance.

On the other hand, if you own a scooter that suits your needs in many ways -- but not in others -- the chances are pretty good that you can make it better suit your needs overall if you approach the task scientifically.

Here's the thing: every vehicle is designed by the factory engineers to a deliberate set of compromises intended to maximize sales and profits to the company. The marketing gurus establish a price point and a set of goals (performance, operating economy, styling, reliability, etc.) intended to appeal as a package to the desired segment of the market. The engineers use these targets to juggle all the trade-offs and come up with a design intended to appeal to the common denominator and produce the most sales with the fewest warranty claims.

However, you -- as the end user -- may well have a set of priorities that don't exactly match the assumptions made by the factory engineers and marketeers. And buying a different model may not get you what you want, either. For example, you may have a 150cc model that suits the 80% of the riding you do in town perfectly -- and you really appreciate the nimbleness -- but it doesn't offer enough top end for the occasional jump onto the freeway with confidence. Or you may want more jump off the line to get the advantage at traffic lights and don't really care about riding on freeways. Or you need more torque to maintain speed up steep hills. Or the suspension doesn't seem up to the task of handling the road surfaces you typically ride on. Or your body type and/or weight doesn't match the assumptions of the designers for a typical rider.

All of these perceived shortcomings and others as well CAN be solved (or at least mitigated) through intelligent modification, but it is neither cheap nor easy. Nor are there guarantees that everything tried will work. And -- as Gordy has stated -- there will be downsides to almost every modification, whether they are simply high cost or difficulty, or performance trade-offs such as degraded fuel economy, emissions, or rideability in heavy traffic.

Some -- if executed well -- offer almost surefire performance benefits. A bigger cylinder kit will certainly give you more torque for fast starts and better hill-pulling, but it will likely not buy you much more top end without well-thought-out gearing changes, and it will come at some cost to fuel economy. High-end shock/spring packages will almost certainly improve your suspension -- but only if they are adjusted properly. Others -- like exhaust systems -- can be very costly, can often produce no -- or even negative -- performance benefit, and may or may not be as durable as stock.

On the other hand, a whole well-thought-out SYSTEM of mods -- while likely expensive, extensive, and time-consuming -- can completely transform a scooter. That expensive performance pipe that produces no benefit when used by itself may help ensure the success of a system of modifications intended to improve the breathing of the engine, such as cylinder head and valve-train modification and carburetor or fuel-injection enhancements.

For many folks, the road to success through mods will not likely be worth the costs. For gearheads like me, however, much of the benefit is in the challenge and the doing of it... so why not?

I have extensively modified several scooters over the years. It was worth it to me and I wound up with a scooter that much better suited my needs, but it was both expensive and time-consuming. But probably not more so than golf or skiing.

I would just add one comment to what SilverStreak said. Sometimes the manufacturers are guilty of horrible conpromises that have a big impact on performance, such as using the same cylinder head for a whole range of modls from 126cc to 300cc. I can only imagine that they have some sort of agreement with Polini, Malossi and the others to leave plenty of room for aftermarket performance products.

I have extentively modded my GTS, for similar reasons to SilverStreak. I enjoy it. The reliability is stll there, but the fuel economy has suffered a bit. However, I am retired and only ride for fun. I do not use my scooter for daily commuting.

Mike

When I changed the belt for the first time on my GT200 I installed Dr Pulley sliders. The scooter seems to accelerate a little better and I have gained about 5mph on top speed. I do think my mpg has suffered a little. Stock rollers were 10.7 grams(iirc) and I think I went with 10gm sliders.

No. I've spent close on two grand on the 190 now - and all the wrenching was done by me - and it's still not the mofo Hyabusa slayer that I want. However, I've had a lot of fun and learned a lot so I think it has been money well spent from that perspective.
As Dave (Silverstreak) has pointed out many times,the inherent problem with the LX is the lack of a 4 valve head.
I can throw all the bits I can buy at it and spend hours changing clutch spings, variators and rollers but I don''t think it will ever make a huge amount of difference.

I still love it to bits though

The 190 and upgear on our LX transformed the bike. Not faster than a GT/S but perfect for around town and even some limited freeway use.

The upgear I did on my GT was fantastic as I mostly took it on the freeway. Allowed me to do 84 on the flat. Also did the leo vince pipe but that was more to eliminate the muffler bearing.

The mods on my LX with GT engine, well I would not go that route again but as I'm this far I'll keep at it.

In all cases tuning the variator is the critical (and often neglected) step. No one can tell you what weight rollers will be perfect for your bike, you have to try a range of weights to get it right. Also has to be redone with almost every change to the system.