2018 Aprilia RS4 50 Euro 4 Upgrade Project

[toratora]

Yeah for sure you'll want to do a leak test. Hopefully I'll have the tutorial written up for it by then, but if not there are some posts in my build threads about how to go about doing it.

The kit will come with different thickness base gaskets. The instructions should say the amount. The torque settings will say if they are different. Otherwise you can go with standard Derbi specs.

I'm really tripping out about how different these bikes are in some ways. Look at totally different placement of the battery.

[Berkeley]

Thanks Tora,
yeah much more tighter with the battery above the engine.. looks like the other is easier to work on

Only took a few days for all the parts to arrive....... including the torque wrench haha
.

Also metrakit state the squish clearance needed .. will be doing it with the modeling clay technique.

[Berkeley]

what a twat!!!!!

So After Painting the heads ,then fitting them to the bike.. and none of the water sensors fitted, or the water hose either.. Im thinking 'No one mentioned this'?????







The I look to the bottom of the head and thinking .. How the hell does the water get into the water pump???, this is nuts.. So I go online and see Ive ordered it for the derbi senda euro 2 and not 3.Maxiscoot were out of stock and got it from motoscoot and just didnt realise

So is anyone wanting a painted 70cc kit before I try to remove the paint and send it back???

BTW you really notice the difference going to the ali head.. quite a weight saving.

[Berkeley]

Anyway.. the Jolly Moto got a strip down and repaint... Much better.


BTW is this right???.. This is the standard 50cc , the piston is at TDC and there is a massive squish gap.. is this right or am i missing something?

[jkv357]

I would recommend masking the mating and gasket surfaces when you paint - just painting the exterior.

The piston height in the cylinder looks odd to me, but I'm not an expert - so we'll see what toratora has to say...

[Berkeley]

yeah i did think of masking it but saw that was sprayed so thought nothing of it of putting a bit more paint there.

As for the head clearance.. maybe its just another restictor they have put in place???

[toratora]

I just went back to my post to make sure I didn't mess you up. The top end that you got is for the older Euro2 engines (like nearly all the bikes we have here in the States). You need the Euro3 kit, which thankfully is what I linked. I take it you didn't order from Maxiscoot? Oh I see that you said that in the recent post. Looking at the photo you posted of the kit the water spout is clipped so I didn't notice it, although now I can see it there on the very edge of the photo. Apologies.

This sort of stuff does happen. I suppose you could contact the seller, and see what they say. The paint may make a difference to them.

I would guess that the piston in the photo is not at TDC. I say this because look at the marking on the cylinder. It look like there is a darker ring near the top. The piston wash looks strange, but that's probably a shadow created from a flash.

[Berkeley]

Hey tora...
You didn't mess up. The kit you pointed to was right but unavailable. I then ordered it from Spain..in Spanish .. the non Ali one kept popping up ..so was focused on getting the sp3. My fault .. let's see..

Re space in the cylinder.. Yes that is tdc.. I took a bunch of photos as thought it looked wrong as should go to the top.. anyway just thought it was of interest.

[toratora]

Yeah I'm sorry that happened to you—I really should have noticed the spout in the photo. If I was more fluid I'd offer to buy it from you since it would be a nice combination to have around for visitors, but right now I'm dealing with too much trouble to be able to afford nice bike parts.

The Stage6 top end is just too much for people who aren't use to riding bikes with that sort of timing. I read on a scooter group where they mill the cylinder, and head to make it a more ridable combination. Not really sure how that would work without a different piston so I'm unlikely to attempt it on either of the Stage6 kits that I have currently—plus they are lots of fun if you can keep them singing.

I may put the Silver bike back to a stock top end though, so that I have an easy bike for people to ride. Plus it was a lot of fun out riding Groms with a stock bike. This is one of the reasonings behind setting up the track bike with a stock engine. Although, now maybe the track bike will get one of these Stage6 setups next season.

[Berkeley]

Ok cool no worries..
On the site it didn't state euro 2 or 3 engine.. I just assumed 3. Or course the heads look different (now I know) well you learn!

This is the euro 3 kit they offer.. but it doesn't show all parts like on maxiscoot. But being a kit I hope it's the same.

https://www.motoscoot.net/cilindro-kit- ... aggio.html

Whats the difference between the sp3 and prorace kit? Is it worth fitting or does this mean changing the bottom end as well?

https://www.motoscoot.net/cilindro-metr ... aggio.html

Cheers