Learn how to DE-RESTRICT here!! step by step w/PICS!!

[scootnfast]

OK, now that little pipe that had to be cut off... The proper way to do this is to cut it off and re-weld it shut. But if you are like me and welderless, I just left enough pipe to crimp and fold it over. I put the end I cut off into my vise and closed it until the pipe came together. After that I took a pair of vise grips and bent the fold in half. Then I beat it with a hammer until it was completely closed. After that I took a grinder and smoothed it over. I guess some JB weld or some exhaust tape might work also.

[scootnfast]

Now you need to re-assemble the exhaust. You are going to need some new bolts to replace the ones you cut off. I was able to buy the same thread bolts and put them through the nuts that were left welded to the other side of the flange. But if the nuts are messed up on the bolts from the weld, then you will need to grind the nuts off and use nuw nuts and bolts. Use some high temp black paint to paint over all those unsightly grinding marks you made! But it should look like this when you are done!

[scootnfast]

OK, all you have to do now is re-attach the exhaust to your scooter. Be sure to get the gasket between the pipe and the head back in its place.

And that is it for de-restricting! on the mojito, the washer and jet did absolutely nothing to the performance alone. But once the exhaust was done, it made a world of differance.

As I said before, it is a pain in the butt to de-restrict the exhaust, just shell out a couple of bones and buy a high performance for it instead!!!

And that is all folks!!! Hope that it was informative! Man that took a lot of time!!! You can thank me by sending the beer straight to my house!!!

Check out my other postings and how-to guides:

How to install a big bore kit on a water cooled /injected scooter - step by step done on an sr 50 ditech: http://www.apriliaforum.com/forums/s...threadid=10027

How to install a big bore kit on an air cooled scooter - step by step done on a mojito 50: http://www.apriliaforum.com/forums/s...&threadid=9421

How to install final drive rear end gears on your scooter: http://www.apriliaforum.com/forums/s...&threadid=8903

Learn how your variator, roller weights, clutch, and contra spring work. And learn how to get the best performance by making them all work in harmony here: http://www.apriliaforum.com/forums/s...&threadid=8960

And to finish things off, I will let you see the license plate frame I made for my little pride and joy!!!

[blackadder]

brilliant piece of work....and I'm sure many a scooter will go 'like' now because of it!

[Paul_84]

First start by removing the socket head cap screws to remove cover on the left side of the scooter... Be careful of the gasket, my mojito had a gasket, but my ditech didn't. Ignore the remove kick start in photo... I am used to working on motorcycles, and the kick start is actually attatched to the crank and you have to remove it to get the cover off. But on these scooters, you DO NOT have to remove the kick start.

[DRT-Tuning]

My friends brother has a Mojito (called Habana over here) and yes you do not need to remove the kickstarter off (any scooter) sinds it's on its on shaft in the cover.

Anyways I also looked at my friend's brother's pipe and noticed that the header screws (or flange) are welded on.

So you had to grind them off. It USED to be just bolted on, not welded, so all you need to do was screw of the restricted flange, and get yourself a fully unrestricted flange for very little money. And in case you needed to make it legal again, you could screw on the restricted one again.

And those resonance pipes on the header didn't even exist then. Man these thing suck.

Also the restictor right in the opening of the header used to be able to be just taken out. But later on they went smart there too and just drilled a few holes in the pipe. So while the ristrictor was in, gas just flowed through the (way) too small opening. But while you used to just take it out before, doing so now would mean you are left with a pipe with 3 drilled holes in it, making it useless.

Ow well, luckely we have tons af great performance expansion chambers here


- I left the anoying! kickstarter cover off. It's just a spacer and it doesn't need to air-tight close it, since there is no gas or liquid in the transmission are. (Of course I'm NOT talking about the gear assembly )

[DRT-Tuning]

I'm not sure but older minarelli styled scooters also have a rubber trumpet resrictor in the air-box. It's in the air intake and can be pulled out without opening it.

Not sure if mojito / SR DiTechs have such a thing.

[scootnfast]

My mojito did have a trumpet on it, but it didn't telly make any differance when I removed it. I don't think it is restricting at all.

[DRT-Tuning]

Well it is a restictor, since it restricts air from getting in. But yes on a stock (or de-resticted scoot) it won't do much.

But if you get a larger carb (on a larger cilinder) you need more air and not everyone likes those open air filter. So most drill the cover of the air box. And of course remove the trumpet.

(Minarelli LC air boxes, that are placed in front of the crankcas, I have a nice aftermarket UFO cross-cover which is drilled and has a removable cover on the allready-tuned cover. So you can nicely adjust air-intake size.

A rare item though. I'll try make some pics.

[blackadder]

I was checking out your idea about fitting a larger injector which makes sense, I have ordered one now to come with my new exhaust, but I've been told that 'raising the needle' at same time will be beneficial. Can anyone explain why... and how to do it?
thanks team.

[DRT-Tuning]

1: A needle has a couple of notches in them. In one of them is a e-clip. The needle rests on this e-clip on top of the slide. So when you lower the e-clip a notch, you ligt the needle and putting the e-clip on a higher notch will lower it.

2: There are many types of needle and they are all shaped differently: the tapper and the straight part. The tapper can be very steep or not.

The shape effects how fast fuel is added to the air rushing through the venturi. A very steep and low tapper will have a more abrupt effect that a needle with a long, smooth tapper.

So the height of the needle also acts as a limiter as of how far the tapper comes out of the emulsion tube. If it can lift higher, the needle will be lifted more out of the tube allowing more fuel to flow into the air stream. And vice versa.

So both needle height and shape effect handling.

It's not always a given that with bigger kits you need to ligt it for more fuel.

Actually I had to put my needle in lowest position (e-clip on highest notch) to have the scooter run smoothly on full-throttle, when I mounted my Evo 70cc cilinder.

Could be because of my needle (W7 needle in Dell Orto 21mm carb).

Everything, main jet size, pilot jet, needle height and type all effect fuel flow and smoothness/ruffness on low/middle/full throtlle.

It can be a pain to find the right combination.

[Modular Overrev]

DRT,

same goes for my Honda50 which has D'O21 carb the clip is on the first notch. if i can fit a needle with less taper maybe i can raise the needle again to the 3rd or 4th groove.

also i've always noticed Dell'Orto jets the idle circuit of their carbs too rich, our D'O21 for example has size 50 idle jet which is too rich so i plan to fix this using IP2's tried & tested method; inserting a fine strand of wire since there's no jets that can be bought for the D'O.

[ApriliariderUK]

Hello, I have taken apart my variator in order to take the restrictor washer off and there isnt one there! I have a completely stock, restricted 03 sr50 ditech which I bought from new. I have heard that 03 ditechs are still resricted in the variator but there is no washer. Scootnfasts ditech is a 02 model so the 03 model must definately be different. Can anyone tell me what is different and how to de resrict the 03 sr50 ditech @ the variator. Also is the malossi multivar sold restricted or de restricted and if it is restricted how, does it have the washer?

Thanks again

[scootnfast]

Hello there... I haven't heard of there not being a washer in the 03' models... Your dealer may have removed the washer before they sold it to you... Some dealers do that. If there is no washer in your variator, then your variator is not restricted. that washer simply keeps the two halves of the variator from comming together all the way. If there is no washer there, then they are capable of comming together all the way, which means it is not restricted.

The malossi Multivar is a performance variator for your scooter... NO THEY ARE NOT RESTRICTED!!! Why would you pay money for something that was restricted??? The after market variators just help with acceleration... But don't expect to get a lot more top end out of them... I have a polini variator, and it seems to work well, and it costs a lot less than the malossi variator.

[ApriliariderUK]

I can only do 35 mph flat out on flat land so it must be fully restricted. When i took the variator off i pushed both sides together but they didnt touch together, there is a 2mm gap between them. Perhaps they made the longer without the restrictor washer there? Would machining the shaft shorte be the answer? How much more top speed would be given by re-mapping?