Hacking an Estoril for higher rpms

I have an 80cc Athena kit on a 505. 15mm bing and a tomos Estoril pipe. Im assuming the pipe is severely restricting the low end power since it cant breathe enough to rev up. My solution is to weld ona 19mm header and install a bigger baffle tube for flow.

Any thoughts?

Re: Hacking an Estoril for higher rpms

Wat?

You have no low end but want to mod for higher rpms that will get rid of whatever lows you now have?

15mm on an 80cc kit is a joke.

I bet you're just crazy lean or there is restrictor washer somewhere.

Re: Hacking an Estoril for higher rpms

Or your clutch is tuned way too low

Re: Hacking an Estoril for higher rpms

Basing off my experience last year when i ran a trail without my exhaust on. It ran way better! Hands down going up hills through some experienced atv trails the bike was great. I get alot of out of the pipe on hills....probably more that the bike needs as its geared as a dirtped with a 11 46 ratio.

My hope is that the bigger header will allow it to rev and the exhaust tube flowing better the bike will not get heat soaked.

Re: Hacking an Estoril for higher rpms

> K Olena Wrote:

> -------------------------------------------------------

> Basing off my experience last year when i ran a trail without my exhaust

> on.

You are super lucky you didn't seize

Re: Hacking an Estoril for higher rpms

I ran for about a mile but man what a difference

Re: Hacking an Estoril for higher rpms

Overpriced Parts /

> K Olena Wrote:

> -------------------------------------------------------

> I have an 80cc Athena kit on a 505. 15mm bing and a tomos Estoril pipe.

> Im assuming the pipe is severely restricting the low end power since it

> cant breathe enough to rev up. My solution is to weld ona 19mm header

> and install a bigger baffle tube for flow.

>

> Any thoughts?

Pipe is the limiting factor pretty much on RPM really no matter what carburetor size you use

I’ve hit 62 Mph with a 15 mm carburetor and tiny 62cc kit (not a sachs engine though) though you will have bigger power gains and a bit more rpm with a larger carb but pipe powerband is The limiting factor,

You got to get a derestricted estroil or cut it open at stinger and remove the funnel inside the stinger so pipe is same inside like outside and reweld it

https://www.mopedarmy.com/wiki/Estroil_modding

Someone else posted my pictures from a photo website instead of directly and now are gone,

I will look for original pictures

You can also shorten header on your pipe but that removes lowend which a sachs needs, bigger carb increasing the power dramatically will just make a sachs clutch slip and glaze over,

Re: Hacking an Estoril for higher rpms

I think my clutch is def an issue when warm.

Can i adjust the clutch preload to get more slippage?

Re: Hacking an Estoril for higher rpms

More slip on a sachs clutch will not be good for you.

Re: Hacking an Estoril for higher rpms

The clutch,engages good i think but when warm it doesnt spin. I have another clutch but i dont want to use it just yet.

Im gonna adjust the preload and report back

Re: Hacking an Estoril for higher rpms

Tweaker trash /

> Overpriced Parts Wrote:

> -------------------------------------------------------

> > K Olena Wrote:

>

> > -------------------------------------------------------

>

> > I have an 80cc Athena kit on a 505. 15mm bing and a tomos Estoril

> pipe.

>

> > Im assuming the pipe is severely restricting the low end power since

> it

>

> > cant breathe enough to rev up. My solution is to weld ona 19mm header

>

> > and install a bigger baffle tube for flow.

>

> >

>

> > Any thoughts?

>

> Pipe is the limiting factor pretty much on RPM really no matter what

> carburetor size you use

>

> I’ve hit 62 Mph with a 15 mm carburetor and tiny 62cc kit (not a sachs

> engine though) though you will have bigger power gains and a bit more

> rpm with a larger carb but pipe powerband is The limiting factor,

>

> You got to get a derestricted estroil or cut it open at stinger and

> remove the funnel inside the stinger so pipe is same inside like outside

> and reweld it

>

> https://www.mopedarmy.com/wiki/Estroil_modding

>

> Someone else posted my pictures from a photo website instead of directly

> and now are gone,

>

> I will look for original pictures

>

> You can also shorten header on your pipe but that removes lowend which

> a sachs needs, bigger carb increasing the power dramatically will just

> make a sachs clutch slip and

If you want to start talking about restrictions I would start at the small ass opening

Re: Hacking an Estoril for higher rpms

And exhaust baffle is terribly restrictive i think.

Re: Hacking an Estoril for higher rpms

Tweaker trash /

> K Olena Wrote:

> -------------------------------------------------------

> And exhaust baffle is terribly restrictive i think.

Exhaust restriction is based on if it’s sufficient enough for the motor’s demand. My riva jog scooter with a next to stock tune will hit low 30s with or without the silencer but without the silencer my low end sucks!

Re: Hacking an Estoril for higher rpms

Overpriced Parts /

> K Olena Wrote:

> -------------------------------------------------------

> And exhaust baffle is terribly restrictive i think.

Not at all restrictive it’s completely clear, It’s just quiet because it exits to the ground, years ago techo circuit exhaust were rumored to be restrictive in the silencer but I never got one that had a restrictor in it they were mostly like that for European use

Re: Hacking an Estoril for higher rpms

♣Slew Foot♣ /

Once that tiny opening or the fiberglass packing gets tarred up...

I hA've. A sidebleed that I sealed the end no headerpipe restricted only by the throat at the exhaust. the ports bigger than the pipe sound re directed by an upfacing stack bigger in dia than the exhaust port but slapped to the floor of the pipe it's louder for me but as I pass it's quiet at higher speeds I get low end with a piston port

Reeds I use 2 stage boysen to get low

Re: Hacking an Estoril for higher rpms

Are you taking about the 80 Reed kit? They have a pretty conservative exhaust from the factory. Puch or tomos estoril? What kinda rpm are you talking here?

I don't see any reason it can't run with the Bing but I think it would be tough to tune.

Also if you haven't replaced the steel reeds do that right now, they will break and can send metal shards through your engine

Re: Hacking an Estoril for higher rpms

I've actually been thinking the same thing. How about shortening the header, there isn't much to cut out but you could probably hack off like 2 inches and get the pipe close to the stator cover. Wouldn't that open up some rpms ?

Re: Hacking an Estoril for higher rpms

Dirty30 Dillon /

> K Olena Wrote:

> -------------------------------------------------------

> Im assuming the pipe is severely restricting the low end power since it

> cant breathe enough to rev up.

I think you are conflating two things, like JBot said. If you want a lower power band, aka pull from a stop, you want a longer tuned length. A shorter tuned length will make your pull from a stop worse, but your hi-end better.

Without pictures, its hard to tell what you are working with. You may have just welded an estoril onto the end of your stock, complete header, which is why you are discussing increasing the header size. Either way, post a pic so we have a better idea what you've done.

Re: Hacking an Estoril for higher rpms

Heres my pipe.

20200415_131820.jpg
20200415_131831.jpg
20200415_131847.jpg

Re: Hacking an Estoril for higher rpms

♣Slew Foot♣ /

Okay mine the baffle broke off and I used a stock Tomos a35 Hunter as the flange donor so it's small. But the rest is wide open the pipe works the chamber the hole where the baffle was got a 28 mm id. The flange 20 mm id 14" tall bolted end.

20191012_180337.jpg

Re: Hacking an Estoril for higher rpms

♣Slew Foot♣ /

Works best with smaller carbs under 18 mm

Top end extended power band it hits the zone around 40. No internal header but I got a wicked hook on the flange.

Re: Hacking an Estoril for higher rpms

Wow thats a nice exhaust hole!

20200415_151325.jpg

Re: Hacking an Estoril for higher rpms

That pipe looks haggard as shit but it's not your restriction point, like I said those kits don't rev very high from the factory. I was geared like 11x 38 on a single speed, just barely around 50. My guess would be like 8500 ish rpm? This was like 7 years ago going by memory. Then I ported and went to a 13 front and saw 60 once on a 2 speed but couldn't keep the clutch together.

I would look at other stuff like the chain line/ motor twisting, tuning, etc. Also get some real speed data/RPM and post back.

Re: Hacking an Estoril for higher rpms

Tweaker trash /

What is the size of the header in mm

And ya ouch! You ever heard of a grinder a bbq paint? U can use jbweld on the welds closer to the expansion chamber to clean them up and seal good

Re: Hacking an Estoril for higher rpms

Jb weld causes cancer when heated...

As for the shittt weld i must say im backtard af.

Re: Hacking an Estoril for higher rpms

Im running a Tomos Estoril exhaust.

Re: Hacking an Estoril for higher rpms

♣Slew Foot♣ /

All the cancer was baked off 5 years ago. That just stopped the hole from expanding and I interference fit the stack.

Re: Hacking an Estoril for higher rpms

What do you mean interferenced the stack?

Re: Hacking an Estoril for higher rpms

I have become more stupid reading this thread

Re: Hacking an Estoril for higher rpms

♣Slew Foot♣ /

Hot pipe cold stack oversized. It will never come back out.

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