Re: Derbi flatreed engine un/restricted

Here is the tjt vs the stock vario. The tjt will let the belt go down into the V more vs the stock one needs to have .085-.100's removed. You see can in the picture that differance between the two. I will weigh the tjt vs the stock vario and vs my modify one I had lighten. (edited)

Picture 381 (Medium).jpg

Re: Derbi flatreed engine un/restricted

Downhill Harvey (OFMC) /

Re: Derbi flatreed engine un/restricted

bump/

after reading.

seems like the hot shit is

no pedal fuction, lose the weight inside gearbox

lighten clutch bell he took .010 from the inner bell (this prob affect clutch grab) and take .032 from the OD of the bell.

vario, take 50 grams off the variater (im only gonna do this if i can continue to use the grease shield)

rear pulley "I had .110 removed/cut from the inner/top of the pulley to make it have more low end. The cheeks are closer thus making the belt start high on the rear contra pulley"

also, get a TJT or Machine the front to match the gearing gain in the back.

"The tjt will let the belt go down into the V more vs the stock one needs to have .085-.100's removed."

Re: Derbi flatreed engine un/restricted

Nice reading work Sabat, you earn a gold star for the day. Now, are you ready to execute?

Re: Derbi flatreed engine un/restricted

yeah, i think i can lay the pully bare on the mill table with two or 3 v blocks holding it to the middle, clutch bell in a lathe would be easy, but the variator seems the hardest to hold.

Re: Derbi flatreed engine un/restricted

ya steven, you can use a couple of the mod's on your pp/pr engines. the tjt and the mod vario is the same weight.. oddly enough. so I need to go back and remove more from the stock vario.

Re: Derbi flatreed engine un/restricted

Removing them starter clutch shoes is one of the best things I have ever did to my derbi this weekend. Here is the pull starter I found in spain works with hpi mini and internal. Rips, really hard without them starter clutch shoes. I should of went pull start a long time ago.

(edited)

Picture 018 (Medium).jpg
Picture 019 (Medium).jpg

Re: Derbi flatreed engine un/restricted

so you just take the shoes out? and thats all? theres no spacer needed or anything? also an electric start would work just as well as a pull start correct?

Re: Derbi flatreed engine un/restricted

yup, as long as you can start the bike other then pushing or pedaling it.

Re: Derbi flatreed engine un/restricted

that rules ed. looking at doing this to my flatreed eventually...so tempting!

Re: Derbi flatreed engine un/restricted

derbeez ryderz /

That's so weird I was looking into making something like this for my Derbi. I like the idea more than drill starting. Plus, no starter clutches is one of the best mods.

Re: Derbi flatreed engine un/restricted

Ed, did you end up knocking out that whole window to be more like the later flat reed engines?

I have the restricted case on my flat reed as well, but I didn't cut out the whole intake. I just opened mine up to match the flow of the intake/reed cage since I'll be keeping it with the stock reed cage.

Re: Derbi flatreed engine un/restricted

Nope, I didn't remove the restriction from the cases, still running it today, runs amazing as you can hear the start up in the video.

No more of that weird down shifting crap, yay! I just love it now.. kill the ignition and coast in quiet. Really nice clutch stall off the line with the 80% stronger then the tjt red springs. Now since the starter clutch shoes are gone its really smoother. Really was being held back with the starter clutch shoes. Ryan, told me a while ago about how much of a change it will make.

Re: Derbi flatreed engine un/restricted

HI ED!!!

Re: Derbi flatreed engine un/restricted

my 2000 Revo StartV motor had some restriction. it's been removed

(edited)

Re: Derbi flatreed engine un/restricted

my 2000 revo startv engine is non restricted design of cases. Hi ryan, Thanks, max

Re: Derbi flatreed engine un/restricted

considering how the stock 2 petal works in there, it may have actually just been a stuffer for case volume, but it's gunna get a big custom block soon anyway. needed to go

Re: Derbi flatreed engine un/restricted

So, the derbi gpr cylinder bolt spacing is all most the same as the derbi pyramid cylinder stud bolt spacing. The DS50, SL, SLE engine cases have this bolt spacing built into the cases. Just check out the pic of the pyramid base gasket on the gpr cylinder. So you can really make the gpr cylinder fit on the 1st gen engine cases. This would not work on a world champion engine cases.

(edited)

Picture 250 (Medium).jpg

Re: Derbi flatreed engine un/restricted

"So you can really make the gpr cylinder fit on the 1st gen. flatreed engine cases."

Re: Derbi flatreed engine un/restricted

Caleb macguyver-keller /

Mo Peds Wrote:

-------------------------------------------------------

> "So you can really make the gpr cylinder fit on

> the 1st gen. flatreed engine cases."

^^ has anyone made this happen yet... or......

Re: Derbi flatreed engine un/restricted

in for future updates. wish i would have seen this thread a week ago when my flat reed was apart!

Re: Derbi flatreed engine un/restricted

Mo Peds Wrote:

-------------------------------------------------------

> Nope, I didn't remove the restriction from the

> cases, still running it today, runs amazing as you

> can hear the start up in the video.

> No more of that weird down shifting crap, yay! I

> just love it now.. kill the ignition and coast in

> quiet. Really nice clutch stall off the line with

> the 80% stronger then the tjt red springs. Now

> since the starter clutch shoes are gone its really

> smoother. Really was being held back with the

> starter clutch shoes. Ryan, told me a while ago

> about how much of a change it will make.

So ,does this mean it is not necessary to remove the restricted part in the case,and it will run fine with it left in the case if your case is a restricted case?

Re: Derbi flatreed engine un/restricted

Overpriced Parts /

Joe West Wrote:

-------------------------------------------------------

> Mo Peds Wrote:

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

> -----

> > Nope, I didn't remove the restriction from the

> > cases, still running it today, runs amazing as

> you

> > can hear the start up in the video.

> > No more of that weird down shifting crap, yay!

> I

> > just love it now.. kill the ignition and coast

> in

> > quiet. Really nice clutch stall off the line

> with

> > the 80% stronger then the tjt red springs. Now

> > since the starter clutch shoes are gone its

> really

> > smoother. Really was being held back with the

> > starter clutch shoes. Ryan, told me a while

> ago

> > about how much of a change it will make.

>

>

> So ,does this mean it is not necessary to remove

> the restricted part in the case,and it will run

> fine with it left in the case if your case is a

> restricted case?

Yes it will work fine as a slow 25-30mph moped

but not as a blaster

Re: Derbi flatreed engine un/restricted

Ken Roff Wrote:

> Yes it will work fine as a slow 25-30mph moped

> but not as a blaster

I just rebuilt my flatreed and it has a restricted case...the bike is a total and complete blaster. then again it is a fully built bike, but I doubt if i would feel a notable difference if the case was opened. Maybe a hair up top on paper due to the increased crankcase volume, but my butt dyno probably wouldn't notice

Re: Derbi flatreed engine un/restricted

OK ,that is what I wanted someone to say.

Re: Derbi flatreed engine un/restricted

Overpriced Parts /

Kyle Mahieu Wrote:

-------------------------------------------------------

> Ken Roff Wrote:

>

> > Yes it will work fine as a slow 25-30mph moped

> > but not as a blaster

>

>

> I just rebuilt my flatreed and it has a restricted

> case...the bike is a total and complete blaster.

> then again it is a fully built bike, but I doubt

> if i would feel a notable difference if the case

> was opened. Maybe a hair up top on paper due to

> the increased crankcase volume, but my butt dyno

> probably wouldn't notice

You running a carb bigger then the restrictor size?

Re: Derbi flatreed engine un/restricted

I didnt measure the size of the opening, but 21mm carb with 19.5mm intake (couldn't find bigger when I purchased it)

so probably....and I hadn't thought about that. But runs great as is. If the area of the restricted inlet is smaller than the area of the intake then I could see some top end gains from opening it, I just feel as though it'd be negligible, but could totally be wrong.

And just making sure, were talking the case restriction post reeds, correct? (edited)

Re: Derbi flatreed engine un/restricted

Anyone have an opened restricted case they could measure the opening of the restriction with?

I'm curious now as to the true volumetric size of the opening, and that size related to a circular intake size.

Re: Derbi flatreed engine un/restricted

Overpriced Parts /

I don't know my spare flat reed engine is normal size intake.

I just thought if a intake is like 19mm(for example)and you put a larger carb on it then 19mm it's like its a 19mm carb no matter what size bigger.

I don't know much more on derbi engines then running stock ones though

Re: Derbi flatreed engine un/restricted

The thread is title for the restriction of a flatreed engine. So, anything that is restricting to it.. will be added. I have been working on another engine. I have many notes to add. Here is another to put under your hats. Autsia reed cage vs stock reed cage. One huge hole! instead of.. 2 petals. ^ fastfreddieswoopie hooked me up with his last reed cage. I'm going to mod a stock one and run some equal malossi reed paper in a set.

(edited)

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