Tomos 74cc APN4/4L 5 Speed Engine Build Timelapse 

It would not get you far with 74cc cylinder. Those engines are notorious for crankshaft failures of any power modification is done.

@@dusanboss7749 @Dusanboss That's why he installed a rito aftermarket one👍

Tomos ctx?

@@matijajerman2005 Nope, a T4L from 1973 modified to T5L, a Dutch model. In your country it is know as APN 4

Hey dude, awesome! I remember commenting with you about the clutch and my 5 disk clutch prototype. I ditched that idea and going to try this setup first but I'm guessing those plates won't last long at all. How long do yours last? When I have it running I'll try porting it too. Thought about a spacer in between the cylinder and the crankcase. How did you do it? Thanks for the love! Much love back to you!

@@Tomology My clutch is holding up fine. No slippage whatsoever at any rpm/load. Pretty amazing. Im at the moment running the cheap universal ones for puch/tomos with straight tabs and they clack ALOT at idle even with a brand new clutch cage but cant find the real tomos with bent tabs in Finland. Usually a set of the cheap ones last about 700km with my driving style and 70cc kit before the tabs have worn down to 3/4th of the original width. One thing is for sure the original clutch plate style uses a more harder clutch material than the aftermarket style so its an consern. At the moment i can do a 3rd gear 10000rpm clutch dump against a wall on asfalt and the engine will stall before the clutch slips 😅 One thing i will do when changing cage and a new tomos clutch plates is to weld piece of lathed pipe around the outermost edge of the clutch cage. I think im going to make it about 1.5mm thick and tack it with a tig. I have seen on a Finnish forum a guy that had a 80cc Honda CR cylinder? and the outer lip of the cluch bent like a flower but he was turning 16000rpm with stock clutch 🤔😅 One thing with the piston ported cylinders is usually they have "booster" ports at the back of the cylinder and that interfares with lifting the cylinder because the intake will be exposed to the combustion area and it will run like crap. I did try it by lifting 1.5mm and it exposed 0.5mm and the cylinder was junk. The way i "mill" down the culinder head surface is by just measuring with a digital caliper the length from block mating surface to cylinder head surface and gently using a table belt sander having the cylinder upside down and rotating it. Then measure each time each corner of the cylinder how much i need to take off. I use 40 grit sandpaper and its a nervwracking because of the nicasil if it chips but i have done 2 cylinders and no chips in cylinder liner. When i got the desired height i just do it by hand and use 120, 240, 320 and wet 400 sandpaper on a flat surface to get it smooth. Usually takes about 1h of belt sanding and 20min of manual sanding. Its a bit sketchy method but i use what i have 😅 Just be sure to use a belt sander with a belt as wide as the cylinder. 😎

Ci BB

hahah tja! soms heeft ook een tomos wat liefde nodig :D

Nece bit nis posebno jer decko nije ni glavu obradio, i momak je iz nizozemske pa te nis ne razumije :(

@@jura1807 google translate helps me out. it's not perfect but it gives me some understanding of what people are trying to tell me :)

I use engine oil instead of grease.

temp difference is key. pistons are very easy to get and around 25€ so not that expensive. to get max performance you need to cut 3mm away and when cutting the piston it is going to interfere with the piston ring. In my opinion porting the cylinder is the best way

@@Tomology Yes it is. I toss the bearings in the freezer myself. Takes a little longer, but works well! Ah. When it's that much, you're right. Gotta cut the cylinder.

I toss m in the freezer too but I've had some times it wasn't cold enough so with this freeze spray it works great

yeah it's an option I considered beforehand but I figured it would work with some quality bearings. and if it breaks within 2 weeks, it atleast was a nice learning experience :)

@@Tomology Okay :-) I was on the same learning with better quality bearings back in those days ... :-) Now i am smarter than before, because i see the mistakes that people in the factory design/construction did . Have a nice evening :-)

voor zover mijn research moet de koppeling het kunnen houden alleen is slijtage een groot probleem. we gaan het zien en anders maken we zelf wel een koppeling!

@@Tomology slijtage heb je natuurlijk altijd, als hij maar niet begint te slippen!. ik rijd nu met een met een 65cc en heb ook zon gevoel dat mijn koppeling het zwaar heeft.(2bak automaat)

@@stormtorcque9247 dat klopt, maar ik heb geen zin elke 500km de platen te vervangen hahah

Je kunt er nog een extra onbeklede plaat bij leggen voor extra druk. Het is wat lastig monteren, maar het gaat wel. De koppeling zou best veel moeten kunnen hebben. In het E90 blok van Tomos zat volgens mij dezelfde koppeling.

gracias amigo!

dat dacht ik :D

I'll look after the squish gap and other stuff when the bike is near its first start!

I got it from a local shop and parts where indeed pretty hard to come by

@@Tomology Waar heb je de krukas kunnen kopen als ik vragen mag? ik zoek er nog een

@@svenvanbeek5487 bij rinkytoys al meer dan een half jaar geleden. helaas zijn ze daar nu uitverkocht

@@Tomology ah balen

Hvala! nadam se ovo ljeto :)

it's cheap, does the job but certainly isn't the best quality out there

crankshaft and those parts are very rare unfortunately. I got the ignition from puchshop

frco moto

nee klopt, ik zag het destijds verkeerd. in de nieuwe video zit ie andersom!

poging gedaan tot importeren maar zonder succes. heb na een jaar wachten heel veel geluk gehad op marktplaats :D carterkap zit een abs prop in

@@Tomology Ik ga binnenkort ook een 4l blok reviseren, kan ik jou misschien ergens makkelijk contacteren als ik vragen heb?

@@svenvanbeek5487 info.tomology@gmail.com

not yet, but very soon! stay tuned

this particular engine is from a 4L and the 74cc cylinder is from a Puch

I stripped 3rd gear; see my community post. and so far nothing else but it's waiting for it to happen :)

ma gledao sam ja. razletili mu se lezajevi ovi na radilici i normalno da mu je puklo zvono od lamele.. razletila se korpa od kvacila

thanks! I had a lot of problems welding the ports because the metal became very porous hence why I used liquid metal to make it smooth

@@Tomology ahh, ok.. i did not see that you were forced to weld the crankcase, i thought just have to wide up the ports a little bit

@@mx125dave yeah, it's hard to notice in a sped up video ;) had to weld and remove some material to make it match the ports on the cylinder

@@Tomology good job!

jb weld metal epoxy

thanks, destijds was ik in de war met die mvt en had m op 1.5mm voor gezet maar dat is te weinig en ik vermoed dat ik daardoor ook een warmloper heb gehad

komt er zeker nog aan, maar moet nog o.a. nog een spruitstuk, uitlaat en een hoop ander spul maken voordat het mogelijk is :)

En, gelukt?

eerst schuren tot hoge korrel en daarna met een wat hardere schijf en bruine pasta en als finish een zachte schijf met blauwe polijstpasta. heb het alleen niet echt gefilmd. koppelingsplaten werd ik al eerder op getipt en zitten inmiddels al goed. thanks voor het opmerken!

Radilica nije od apn4 nego jedna od kvitetnijih, ako ne i najkvalitetnija radlica za apn blokove, rito race :) i decko je iz nizozemske pa te ne razumije :(

hey parts are rare over here too. bought a few parts in a store called rinky toys and a lot is from the second hand market and local dealers who imported stuff from slovenia. outsourcing everything took me about a year. the cylinder is from a puch and therefore has different intake and exhaust port positions. I have not started it yet so can't update you about the clutch atm

Hello david, send me a DM on my instagram account “@gh.racing” I can help you find all the parts that you need.

Is your moped Solifer? I had here in Finland Solifer SM-79. It had a 4 speed gearbox. I bought 5th conversion kit 36 years ago, but I have not that moped any more

@@larrymanfred4811 terve. Tää on solifer sm86 Olen ruotsin puhun pieni suomalaiset:)

really don't know either. it depends on a lot of things. my best guess is between 8 and 12hp but maybe more if the setup is right?! have to put it on a dyno one day!

Sory right now I now

From your video

@@borisvanic7339 in my case it's 0.3mm shims on each side but be sure to measure it. allow about 0.1mm play between the crankshaft and the bearings and be sure it rotates smoothly. any more play than that should be compensated with shims

@@Tomology ok, thanka

I don't know. I'm not a scooter guy and have never worked on one.

absoluut

in the Netherlands it's a rare part

oh well i'm from slovenija so if you need them i could proabably get you a couple@@Tomology

I'm from the Netherlands

I bought a lot at local shops and parts were very hard to find

alles is mogelijk, maar het is niet makkelijk en je hebt fatsoenlijke tools ervoor nodig. ik heb zelf een heel nieuw onderframe uitgetekend en lasergesneden en eronder gelast. de ophangpunten van een 4L blok zijn anders, de breedte van de blokophanging is 60mm ipv 50mm bij a35 blokken en je zult je achterbrug aanzienlijk moeten verbreden zodat de ketting recht loopt want het VTW van een 4L blok zit heel wat meer naar buiten!

@@Tomology weet jij toevallig of het dan makkelijker is om m onder een puch of tomos want je ziet best wel veel puch maxi's rondrijden met een 4l blok

@@radio-180cc geen idee maar ik ga er vanuit dat het alsnog een hoop werk is omdat niks past.

@@Tomology bedankt👍

@@Tomology heb jij zelf zoveel tekenskills en engeneering kunde? 😉

Some high rpm cylinders use only one ring to lower friction

mvt premium

@@Tomology thanks

the 'lubricant' you see is actually freeze spray to make the metal shrink for an easier install

@@Tomology Oh, I did not know this procedure. I'll keep this in mind when rebuilding my engines

thanks I appreciate it!

Je hebt een aantal basistools nodig en een paar kleine extra tools, maar het is zeker thuis te doen!

I'm building a custom cafe racer based of a heavily modified tomos revival frame. Check my channel banner there are some preview photo's!

@@Tomology nice dude keep tomos living the original company shutdown it was like 15min from where i am living and i like that the culture is spreading elsewhere!

@@silvanapehljan3677 tomos culture is big over here in the netherlands!

thanks. it's not an original engine build, hence the non original parts. it's cooled by the wind while riding so forced cooling and a fan isn't needed. this older engine came original with the clutch nut. later models have the crown nut.

​@@TomologyDoes he have a kajla that prevents it from unscrewing while driving and for a cylinder as a kid I put a cylinder of t 15 that cooled the wind happened to me to overheat several times while the factory that has a fan can not do anything

it was a mistake I made the first time I built it.

thanks! yeah few mistakes but fixed those. longevity is indeed not much hahah broke down 3 times within 30km

it was about 220 euro and it delivers 55watts to charge a battery and provide power for the lights

probably not. I will find out very soon with the first testdrive

@@Tomology please tell me when you will try because I have the same engine just need to put it together with the same cylinder and l am curious about that clutch

@@anzeahac523 I'll try to remember, but from what I've read online the clutch can hold the power with 3 plates and 6 springs but it wears out in about 250km

@@Tomology thank you very much...do you know is clutch from newer models with 4 plates is better? And 6 springs?

@@anzeahac523 I think so, but I guess it will wear out fast too

probably not because manufacturers switched to the bearings that are the standard today

I prefer L17 above 'normal' solid bearings. L17 has the ability to set and adjust itself a little bit, which the 6203 bearings wont do. Tomos changed the design because L17 bearings are more expensive and need more attention to shimming.

@@SwiffMeister nice to know!

local shops and collectors. took me almost a year to get all the necessary parts

it's a Tomos 4L or APN4 engine with custom parts. you can buy those used. over here in the Netherlands they are quite rare

@@Tomology it doesn't look too complicated why don't you use a generic 4 speed honda gear box and case then make a custom jug and head to replace that old unreliable rare engine with cheap off the shelf parts

@@charliesybert2683 because it would be another boring other brand engine swap. It's a challenge and using an original Tomos engine on an original Tomos moped has value to me

the cylinder is a 74cc airsal for a puch not an e90 cylinder

Ok thank you maby I will buy that kit for my apn 6

Is it worth buyng it ?

@@diegoladavac780 it's relatively cheap and performs well so I guess. I hope to test it out soon

buy them online

the crankshaft isn't stock

rito crank