Modern Vespa

I would like to know from GTS 250 owners or anyone with first hand knowledge of this what are the best weight to put in my GTS 250ie



my aim is to achieve a little more take off speed and maybe a touch more top speed but I would be more than happy with no loss of top end and a modest gain from 0-30mph...

its a 2007 GTV with less than 6k on the clock, as I have the service manual i know its had a first service and an intermediate,but the shop have as of yet been able to tell me what exactly has been done, if belt and rollers have never been changed i'm aware this will probably make a difference all by itself as although the bike hasn't done many miles the belt and rollers has still been through 5 winters, same for plug and air and oil filters I would imagine..?

once again sorry for raising this again but having searched through previous posts i have been unable to find a definitive answer...


many thanks in advance for your help

I have 12g sliders and really like them. Good take off speed, lower revs at higher speeds, and higher top speed.

I liked 11 grams i the Piaggio variator, 13 grams in the Polini variator.

Mike

With the sliders you want to go 1 gram lighter....that means 10 gram sliders for the 250 quasar.

That's what works for me.

Your mileage may vary.

R

Well, there you have it! !0 grams. No, 11 grams! No, 12 grams!

The experts have spoken!

Mike

i like 11 !!

I bought 12g and regret not going lighter. I'm actually putting the standard weights back in this weekend to decide which is best. I suspect I'll end up getting another set of lighter dr pulleys.

Thanks for all your replies...

I think I'm gonna get a set of 10 and a set of 11...

And mix the two..three of each giving me 10.5...average...


I'm also gonna get a nkg iridium plug mallossi air and oil filters..

Staying stock on the belt
Also considering going to a 140 on the rear tyre.....Pirelli Diablo..

I will post the results when it's all done..!

I have the mix 10 and 11 - wanted a bit more bottom end - not sure if it worked really or not. If you want to notice it then I guess 10 all round may be better. Next time I change I will probably go 10 all around.

Remember to alternate the different weights (obvious but saying it just in case).

Spark plug probably makes little difference neither does the air filter - though I did do the air filter "mod" which involved cutting a few parts of it out to allow slightly freer airflow. Not sure where the details of this are - I think it was down to Mike Holland in fact so perhaps he can point us in the right direction.

Certainly stay stock on the belt.

Charles.

thanks charles.....


i recently had a partial service on my GTV 125 before i swapped it for the GTV 250 and chelsea scooters put a champion plug in,it had previously had an NGK


the only other thing done was an oil change i definitely noticed a difference in performance after the service, it was just less pokey, I cant imagine an oil change doing that so am putting down to the plug...

could equally all be in my head though...

maybe 10's are the way to go...cheaper than buying two sets for sure

11.2 is the standard weight so you are pretty much spot on the 10% lighter advised by drpulley.info.shop in germany were i'm buying them...


once again thanks for all your replies...

I went with 10g (Dr. Pulley Slider Weight 21x17 - 10g, UNI-SR-21X17-10g) in the stock variator and have been very happy.

Quicker, quieter, no top-end loss, no mileage penalty.

I bought ten and eleven gram dr p's. Installed the tens and never tried the elevens. I am satisfied with the ten gram sliders. Top speed seems the same, takeoff is much better and I still get between 70 and 75 mpg during the warmer months. Revs are up, but it does not increase noise or use more fuel. The best top speed I have seen is 88/89 indicated on the flat, which is about 80 real world mph. This only happens on the interstate; two lane country roads show several mph lower.

Hi, if Dr.Pulley's SR is installed in Polini variator,please check the variator is molded by die-casting (ie.injection molding) or gravity casting.If it's by gravity-casting then you need to polish the surface of roller runway otherwise the SR might be worn rapidly (ie.the surface roughness of die-casting is much smoother and for gravity-casting it's not so smooth or a little roughened).

By the way,Dr.Pulley's V201503 is a good option to improve the acceleration in all speed range.
Dr.Pulley variator V201503 for Piaggio 125 to 300

Thanks, Dr.Pulley, I will check that next time I have the transmission open. At the moment I am using 12.5 gram rollers in my Polini variator.

If that Dr.Pulley variator is specially esigned for sliders, I am keeen to see the results.

When fitting sliders in a Polini variator, one has to install a "fuzzy" washer as well, to prevent the belt riding too high and rubbing on the transmission casing. That's an extra 0.5 mm spacer an addition to the standard one inside the outer pulley half.

NB. I have a Malossi cylinder and head, and the roller/slider weights need to be heavier to suit it.

Mike

10g is more revy, quit good for take of at red light, may be 10,2 If I can do fine tuning.
Can need some grinding on sidewall because do not slide freely in piaggio stock variator.

went with the 10g


am very happy with the performance, a modest gain at top speed and a major difference in the lower and middle ranges

off the line is considerably quicker 0-40 mph is blink of an eye stuff, now has a nice noticable pick up from 40mph all the way up to about 65mph..

from there on to top speed is nice and smooth maybe a touch quicker than before.

also did the malossi air filters at the same time and the engine certainly sounds louder bit more throaty i like it.....


bottom line a fantastic performance mod for a very modest price i would recommend this mod to anyone..

next stop mike's airbox mod....

Ouch 1000 km later, cost me one belt, one seal 1l of fresh oil, and 2 hours cleaning.

At full speed belt grind carter, burn oil tank seal that leaks every where.





[img]http://imageshack.us/scaled/medium/819/20130320184212.jpg[/img


I don't hnow at wich top speed it begins to grind.

Parkaboy...would you mind kicking in some feedback on how these sliders are working out for you? I'm in need of a service on my GTS 250 and I really like your feedback so far on the 10 gram Dr. Pulley sliders.

Also, what belt are you running? Malossi? Piaggio?

Maybe someone has measured the width of OEM vs Malossi.

I thought I read somewhere that Malossi was wider which would cause it to ride higher and...

Yes, when PM Tuning did their comparison tests, reported in Scootering magazine, they found that sliders with a Malossi belt resulted in oil seal damage. They fitted a thicker washer in the variator to counteract this.
Mike.

It is a public holiday here and I just dug out the PM tuning article and yes they used a Malossi belt for their tests.

Strange because J Costa was in their test and the J Costa manual states that it is to be used with original parts. I.e OEM belt.

Maybe they just plain didn't read the manual.

It seems nearly every "improvement" over oem has a gremlin. I really likes the sliders at first. I ran three sizes. Heck, at first I was so excited i bought multiple sets when I found a deal with really deep discounts. But after a bit and reading about multiple problems I left them to those that can afford, or have the skills to fix bigger problems. I ended being a fan of Piaggio engineers, accepting they were smarter than a vast majority of wrenchers here.

...So was the problem the sliders or the belt? I've heard many say that the OEM Vespa belt is the way to go. In most cases I tend to echo the sentiment of Tomjasz who feels like thinking that we know more than Piaggio engineers is a bit foolish. However, I am open to the idea that some of their work could possibly be improved upon or enhanced. This is why I'm still kind of interested in the sliders.

My GTS 250 that I recently bought used is past due for a belt & sliders. I think I'm going to order Scooterwest's Deluxe Variator Overhaul kit that includes the Vespa belt, OEM rollers & guides, O-rings, a variator nut, and the tools for $173.00. I'm also going to get the T-spinner to remove the nuts on the case (only I'm getting my T from Amazon.) I'm going to stick with OEM parts for now and maybe experiment later. I don't have the cash or time for something that will "probably work."

I have an old VW Super Beetle convertible that I drive & work on. The wisdom of the more experienced VW mechanics is to not second guess German engineering. You see a lot of guys swap out their engine parts for chrome "dress-up kits." The old guys shake their heads and say "chrome doesn't get you home."

I love it.

I've had several instances where running the sliders in a stock vario caused the OEM belt to rub.

Mainly it was during extended high speed runs (freeway riding in general)

Switching to a GT200 belt or back to stock rollers was the cure.

Personally, I'd drop the coin on a polini or malossi vario if was looking for an improvement in that department.

Me I'd use J Costa.

For an LX 150 they actually specify using a GT200 type belt .

I've read about different measurements of OEM belts which means that even with OEM parts there could be tolerances. That alone could partialy explain why some have problems while others don't, meaning with the same engine, all stock + Dr. Pulleys. I have two brand new Piaggio belts coming from Italy and the one I have in my bike is fairly new too (2K), so I will measure them all to see what their measurements are (should be L835 mm, W21.5 mm, H13 mm for Quasar 300)

I tried 3 weights. Sadly I didn't keep notes. The improvement on take of was great in two sizes. But seeing the adventures created for some backed me off. I wasn't a highly skilled wrencher and don't have the likes of Greasy or the expendable cash to have continued. Have the cash? The Skills? Greasy and his mechanical skill locally? Go for it. Want a reliable easy to care for scoot change the rollers at half the recommended and be pleasantly surprised by the improvement. YMMV.

I just ordered two spacers, one 1 mm and one 1.3 mm thick and two extra oil pan gaskets (for the event I will rip it ) from Piaggio dealer. Total cost 10EUR When all the parts get here, I will be ready to experiment

don't forget the cost of a new belt and oil...

see, when that thing rips out it oils down everything and totally saturates the belt thus making it useless. trying to clean the oil out of the belt will only result in damaging it and drastically shortening the service life.

and, yeah on top of all that you have to drain the oil to replace the gasket.

i don't know what the bigger kick in the balls was. having to do the job twice or having to pay for the parts twice...

-g[/i]

The key number is the 21.5 but if the belt is slightly too long it may also cause rubbing. one or two mm is not super critical but....

Yup, keeping that in mind. New belts are coming, but I would rather use an old used one to start with, but I don't have one, mine is fairly new so I'll have to take the risk. I will probably start with two 1 mm distance washers and do the marker tests to see how far the belt rides. Then I'll put only one 1.3 mm there and see how that goes. If there is still enough room I'll try to leave just the standard 1 mm washer there.

All numbers are key in this case, because there is very little room for any slack.

It' like anything mechanical. You can't just expect an aftermarket part to work as well as OEM without certain adjustments. A little bit of trial and error. I know people who are skilled and had the very same problem. Meanwhile I've never run anything but factory stuff in my bikes. I like the reliability and don't mind the usual once-a-season mainetenance day to replce a few factory parts on their roughly recommended schedule.

Same goes for exhaust. These companies have teams of engineers figuring out what the best designs are for flow and torque and things we don't even think about.

Ever wonder why every aftermarket exhaust (but one I think it is?) looks like a fat telescope while every factory Vespa exhaust doesn't? The Vespa team of exhaust engineers know why. Flow is only one part of that equation. And making it the shape of a can is cheaper than the funky shape the folks at Piaggio determined was necessary.

Sure, there are cost cutting measures. And then there are measures which only look like cost cutting measures. Following the maintenance schedule, whether you pay a great shop to do it for ya or you know enough to do it right yourself, is not that hard and not that out of line price wise. We know the payoff is ling term reliability.

I have over fifteen thousand miles on my LX 150. I've done all the maintenance following factory recommendations since it was new. If I really feel I need more of something, I'll get the bigger GTS series.

I don't have time to futz with aftermarket doodads. When I have the time to ride I want absolute surety I'll not only get where I'm going but I'll get back in time to pick up the kids, do the family thing etc.

Maybe the solution to the groove thing is a shaped shim between the two halves of the tranny cover to free up some room for the belt to run wider when it needs it . I'd have to look at it again to see if that's the right course of action.


Harv

Exhausts: Make no mistake, many aftermarket companies take their stuff very seriously and don't think for a minute that they know not what they do. The original manufacturer has to keep emission regulations (very strict in EU for example) and for this reason some bikes may not always perform to their max potential. Some people replace exhausts to get better sound, some just like their design better than OEM and yet others want to get rid of the restrictions to "open up" the engine's potential (along with other stuff, like performance air filters, chip tuning etc). To say that it's no good because I don't like it is just very narrow and simplistic view or not understanding the point. People ARE different and they own their bikes for many different reasons. The whole point is to HAVE FUN with their bikes and for some it may mean to do stuff to them and shape them according to their individual taste.

Hi Dreamer,

You missed my point.

Harv

Sito Plus is the best of both worlds



This one is cute

Two OEM belts just arrived, so I measured their width and height just for the record. Both show the same values and both are exact, i.e. W21.5 mm and H13 mm. I didn't measure the belt's length yet, will do that later.

I have a 2007 GTV with over 49,000 miles on it. I am frequently riding at the top end or fully open. I tried lighter (10g) Dr. Pulley Sliders with great acceleration through 50 MPH or so, but I felt that I had way too many RPMs going on and it was a great strain on the engine at full throttle.

I switched back to the rollers that were put in when I last had serviced (unknown weight, 11g? 12g? ), but going from 60 MPH to 70 MPH felt weak. I really want to be able to accelerate from 60 MPH to 75 MPH much faster without straining the engine. Do y'all think I should go with 12g?

Another concern is whether to go with 20 mm or 21 mm. Whatever rollers the mechanic put in last fit tight and do not roll freely ... at least not all of them, so maybe it's a mix bag. The shop manual states a minimum of 20mm.

Trying to install new sliders 21 17 11g on my 250. They don't seem to fit in the grooves right. I can cram them in but then they don't seem to slide at all. Anyone have the same problem or is this normal?