Re: Derbi flatreed engine un/restricted

Ken Roff Wrote:

> 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.

Couldnt agree more. In theory, you can only flow as well as your worst restriction. Only reason why i feel there is a difference was from a puch setup i had played with. Ran a 19mm carb then switched to 21mm and felt like it was able to make more power at the top end.

I remember in Christophe's thread about the e50 treat reed kit he mentioned the same experience.

@Ed- Cant wait to hear how the modified reed block works out! ive been having a pretty good experience using the .4 tjt carbon reeds on a stock block so far.

Re: Derbi flatreed engine un/restricted

here is some progress from a ds50 engine that i modified. i reramped the ports so they will flow a bit more. i cut out the restriction then making the 3rd eye port flow more surly help to booster power. my fingers/hands hurt from filing and sanding. i'm not done. i have a bit more to file off and polish out. i made the oil feeder holes for the bearing a bit bigger and that will help the bearings get better lube. i have not port matched it to any cylinder yet. i figure the flow of the ports from stock is a bit weird not uniform like most moped cases. very small gains.. yes, but smooth flow of air.

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Re: Derbi flatreed engine un/restricted

so, here is a update on how to lighten your internals. this is for my ds50 project, don't mind the shorten pedal shaft.

you only need these parts inside the gearbox/transmission. i wish i would learn this earlier. live and learn. thank the spain forums! no need to machine the pedal shaft or pedal gears, just remove them and use the factory shims for the shafts. you can even keep your disengagement paw if you would like or pick up one my delete kits. the more you play with the parts the more you learn. i'll update more once i have everything done to the engine im building.

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Re: Derbi flatreed engine un/restricted

So you can run this with the pedal shaft removed? won't there be a giant hole in the gearbox?

Re: Derbi flatreed engine un/restricted

wut? no, you must have the pedal shaft. you have go back up the thread and find the pics and compare maybe that will help ya. i hope it does. i guess i should do a video to explain this.

Re: Derbi flatreed engine un/restricted

here is a


video of the updated. hope this helps explain it a bit better. (edited)

Re: Derbi flatreed engine un/restricted

Here is a comparison of the stock vs modified intake.

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Re: Derbi flatreed engine un/restricted

good stuff Ed!

Re: Derbi flatreed engine un/restricted

this is rad as hell. awesome research ed. i assume the pedals will just spin freely after the delete?

Since you have it posted, how much of a difference between running the lomat vs. the single petal flat reed?

Re: Derbi flatreed engine un/restricted

Andrew Squiggman /

100!

Re: Derbi flatreed engine un/restricted

ok, first pic is another update of showing the guts inside the ds50 mod engine i'm building. the second pic is showing a mod i did to the spacer then it will allowed more oil feed of the needle bearings that are inside the output shaft.

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Re: Derbi flatreed engine un/restricted

Ed you are the best!!

Re: Derbi flatreed engine un/restricted

Nice work Ed I like the video!

Re: Derbi flatreed engine un/restricted

thanks shannon, you're to nice :)

dano, my videos are awful but get the point across i suppose. cheers

thanks, guys

here is couple of veiws of the spacers i modified. i was tired last night and had time today to finish it up to make it pretty.

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Re: Derbi flatreed engine un/restricted

my next step is run one of these over to a local guy to have him machine the od of it. they came in 2 different styles.. ones with roll pins and ones without roll pins. i'm going to have the one machined without roll pins. hope to cut it down to where the paws are. thee deerbi parts are all so dam hard.. ear plugs for sure.

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Re: Derbi flatreed engine un/restricted

here is that clog/paw machine down.. epic! so dam hard.. 1:40 minutes to cut it..yes, with a carbine cutter, just so dam hard and i didn't want it over heated. going custom is a pain in the ass sometimes.. i will still be able to use the 2 springs and 2 ballbearings to keep everything nice and tight.. if you use a roll pin style clog/paw.. you will not be able to cut down very far. now i can actually assemble the engine sometime today or in the next couples days when im bored. :)

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Re: Derbi flatreed engine un/restricted

here is something.. startv vs old style. contra shaft is the same spacing.. and the primary gears are the same teeth count. neat to have the parts to show the difference. probably possible to stuff start5 cranks and internals into a old style cases.

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Re: Derbi flatreed engine un/restricted

Hey Ed, can you comment on 1 big reed vs 2 smaller petals?

Re: Derbi flatreed engine un/restricted

hmm, i would think.. one big hole is a lot better then a restriction like 2 windows.. think of it in a house that wind is blowing through. one big window letting air in.. vs .. 2 smaller windows letting air into the house. big gust flow better through one big window? make sure you put the screen up.. screens are just that a restriction of airflow. (edited)

Re: Derbi flatreed engine un/restricted

GET REALIZED! BE HERE NOW! /

you could also think about the weight/ size of smaller reeds allowing them to react/change direction more quickly. but you also need to think that reeds aren't so much opening/closing as much as they are vibrating at some frequency...

This turns to the 'oil' discussion very fast though....dark arts

Re: Derbi flatreed engine un/restricted

curious to see how it goes with a stock reed cage modification..

Re: Derbi flatreed engine un/restricted

here is another lighten clutch bell but this time i had them cut out the starter clutch pins then had them turn down the face inside and od of the clutch bell. the clutch shoes were out of balance so i matched them to 66.4 grams ea.

also had the starter clutch bell machined off most of the way, didn't want to weaken the posts but still keep some strength.. turned it in a tapered edge.

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Re: Derbi flatreed engine un/restricted

I thought it was also pointed out that once you hit the pipe, your reeds don't really matter anymore. so at that point, not having the split will improve air flow.

Re: Derbi flatreed engine un/restricted

^ i plan to cut the divider out of a set i have laying around for my ds50 and use some reed material.

Re: Derbi flatreed engine un/restricted

i didn't want to make another thread. so i'll stick this picture of the decomp plugged on a airsal 44mm cylinder, i had a piece of alloy rod machine for press fit. now i can use the oring cylinder head, going use a pull starter and i didn't need a decomp hole.

second pic is a minarelli v1hc cylinder head fitted to the derbi. why, angled spark plug. :)

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Re: Derbi flatreed engine un/restricted

ds50 came with z17 ninja star sharp wore out sprocket. i found someone that could lathe, press fit, tig weld it all in one shop. takes a long time .. dam stuff is so hard. 5 hours to get it to where you see in the pic but it spins true. so going from a z17 to a 21t holy sprocket! clears the pull starter cover and the kickstand bracket near the frame. plus i tapped the overflow hole with a air nipple then i could run a hose to maybe catch any gear oil that gets pushed out from high rpms/ high speed runs. getting closer to completing the ds50 build.

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Re: Derbi flatreed engine un/restricted

Nice work Ed post a video once you get it running.

Re: Derbi flatreed engine un/restricted

any reason you went airsal over the metra(airsal)?

what sort of variator/clutch mods!?

Re: Derbi flatreed engine un/restricted

Beautiful Ed

My friend helped me make this pull start + we used the sidecover for a stock look. (maybe I will put the Derbi laurel on the center) (edited)

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Re: Derbi flatreed engine un/restricted

well do dano!

tommy, the airsal was gave to me long time ago as a gift so can't wrong there. i have other 65cc kits, never messed with the 75cc stuff.

very nice, richard! show some inside pics! i have a couple of covers laying around. neat idea! stock cover with pull start is sweet! :)

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