How To Build a 70cc Parmakit Tomos A35 Engine - Street Tracker Build Series Episode One

Tomos Street Tracker Build in collaboration with Tomoshop! This video series is sponsored by Tomoshop.nl! Shop for the biggest assortment of original, tuning and replica Tomos parts here: bit.ly/42FxoAm
Vintage meets modern in my journey to create a Street Tracker moped. Street tracker motorcycles have a rich history that emerged from the world of flat track racing and custom motorcycle culture. Flat track racers competed on lightweight, stripped-down bikes with simple frames and high handlebars for better control. The street tracker style began to take shape during the 1960s and 1970s when enthusiasts started adapting flat track race bikes for street use. These modified motorcycles retained the minimalist and functional design of their racing counterparts, while also being adapted for road riding. The style represents a blend of vintage aesthetics and modern functionality and performance, capturing the essence of the open road and the spirit of urban exploration.
Inspired by the street tracker's fusion of vintage charm and modern edge, I'm building a unique Tomos moped that contains these elements. A lightweight frame, wide street tires, raw two-stroke power, agile handling... Stay tuned as I bring this vision to life with the help of Tomoshop!
Make sure to Subscribe so you won't miss an Episode of this series!
Leave a Like if you enjoyed and comment if you have ideas for the build!
Episode one: Engine Build
Episode two: Frame Build (Coming up)
Episode three: Test Ride & Tuning (Coming up)
Episode four: End Result (Coming up)
Setup and used Tomoshop parts:
-70cc Tomos Parmakit Cylinder (45mm) | Get it here: bit.ly/47MdZRi
-19mm Dellorto PHBG Black Edition | Get it here: bit.ly/3QPDBGI
-19mm Intake manifold | Get it here: bit.ly/3OPG1lX
-Malossi Carbon VL1 reed valve | Get it here: bit.ly/3QUO7MS
-Top Racing A35 crankshaft | Get it here: bit.ly/3qCBTOr
-M-pipes 70cc exhaust | Get it here: bit.ly/3YPmfMa
-MVT Digital Direct ignition | Get it here: bit.ly/3OMPCKu
-NGK Racing spark plug wire | Get it here: bit.ly/44mICK3
-FM Racing A35 CNC Carbon clutch pads | Get it here: bit.ly/45IorHq
-31 Tooth front sprocket | Get it here: bit.ly/45makIe
00:00 Tear down
03:29 Cleaning
04:50 Cylinder overview & plans
05:42 Dremel time!
07:22 Painting
07:51 Bearings and seals
08:31 Clutch upgrade
10:04 Assembly pt.1
11:28 Top end modifications
13:15 Assembly pt.2
17:52 Chain fitment
19:45 Crankcase cover modifications
21:06 Squish & Ignition
22:16 Assembly pt.3
23:32 Test run
Watch my Tomos Café Racer Project: bit.ly/44mFn5p
Watch my Tomos A35 Content: bit.ly/3YJFneq
Social media:
Instagram: tomology74
Contact:
For business inquires only, please use this email: [e-mail]
Disclaimer: Building and modifying engines and/or mopeds require technical skill and safety precautions. Try at your own risk!

[@GoogleAccount-tt5yx]

finally somebody let you out of your cage! of course i am kidding! This is my favorite tomos channel! Keep up the good work master!

[@Tomology]

hahah, thank you. I will!

[@Bu5h1d0o0]

Nice to see you again, hope the post-op recovery goes well and hope to see more videos in the future!

[@Tomology]

thank you!

[@joppy232]

i love that testbench you made for breaking in engines!

[@GravitySandwich]

What a build! Very curious to see future video's about this one!

[@KyleMoto]

dayum dit is genieten. wat een perfectie 😍 ben beniewd hoe hij loopt straks

[@Tomology]

goed om te horen! ben ook zeer benieuwd.

[@tomoscrewnederland8454]

Haha ja het tegenovergestelde wat jij vaak doet 😂😂

[@Tomology]

@@tomoscrewnederland8454 lol

[@thedistance8843]

Very beautiful, keep up the great work brother! Your hard work and dedication is well appreciated and recognized. 👏👏 well done! ❤️

[@Joschi746]

Super built 🤩

[@PHUSII]

Ok that is the biggest front sprocket i have ever seen! :D. Lets see how it will sing!

[@dorinabontemps6032]

This modification make your bike like jet fighter

[@blazkorotaj3515]

I designed this clutch. It is amazing!

[@eriio4056]

Good to see you doing another engine mod as always amazing job👌👌

[@alexandarvidic]

Work of art, well done

[@Tomology]

thank you! :)

[@FriendsWThoughts]

Looking awesome my friend! Glad to see you back

[@Tomology]

thank you :)

[@antoniobarrena6996]

Essa pessoa é entendida daquilo que faz, trabalha com conhecimento e precisão e os meus parabéns.

[@bero7488]

nice detailing build,im interested how will run at 31/22 gear ratio on next video!

[@Tomology]

me too!

[@nicodereus5424]

This makes me happy , clean build 👌👌

[@Tomology]

Thanks! Your comment makes me happy too :)

[@BillyBob-uc9zp]

Nicely done Mr 😎

[@maremare9515]

After a long time again . . . 👏👏👏

[@Andriesdemotorrijder]

mooi zo'n 3d geprinte houder voor je blok!

[@doglegjake6788]

Excellent video

[@aligm3838]

Clean work 🏆👍🏼

[@Tomology]

thank you!

[@virakduong1466]

Thanks so much for your video. You are the best ❤️

[@Tomology]

thank you! really appreciate it.

[@KenzertYT]

I think the pinging may also be 24:07 the loose washer and nut on the crank :P

[@aleksandarmircevski9975]

the idea with the thickening of the walls is great but saw this a bit too late i needed this for the boost port on my tomos atx that i moded to fit a 75cc kit for minarelli vertical

[@Tomology]

well, now you know for your next build! ;)

[@carrestore]

beautiful good job

[@Tomology]

thank you :)

[@rudolfjozinec]

Vidim ovdje jako puno truda i vremena i puno dobrih rjesenja. Jedino sto mozda nebi bilo lose da je umjesto tekuceg metala nekome dat da jnavari aluminija. A brate ova flandja od frgazera s 2x90 stupnjeva mi je ko prstom u oko :)

[@Tomology]

The metal epoxy works well for this application. And yes, the intake is not ideal ;)

[@1marcelfilms]

I remember having one. Never needed any service for years until i sold it

[@Tomology]

Stock ones are near indestructible!

[@carllinden533]

Does this have a two-speed that functions how I think it does? If so this little thing is ingenious!

[@Tomology]

I can't read your mind, but it is a dual clutch two speed transmission and it is pretty neat ;)

[@marcelodibenedetto276]

😮 excelente!!

[@dale5303]

Awesome to see this, i still have my 2005 tomos LX yellow and black i bought new. They were awesome to have in the nj/ny area

[@youneverknow111]

my colibri 14 is 51 years old

[@arturogvasquez6438]

Exelente maestro muchas gracias.

[@Tomology]

Thank you!

[@SuryoAsri]

Terimakasih sudah berbagi viseo ini Saya jadi bisa belajar. Salam sejahtera

[@thebear6529]

sick!! if I was skinnier I would love to have some mopeds

[@youneverknow111]

hhaha im 114kg and moped 55kg

[@bachhoang736]

so cool

[@pkuula]

Nice video, greetings from Finland! Motip engine paint is my faforite paint for this kind of aplication. Im building Old Puch engine with JPC Autisa 65cc cylinder and had to do same kind of job for engine cases.

[@unhiptser]

Just subscribed man that thing sounds serious

[@Tomology]

thanks!

[@lukac267]

tomos motor moje mladosti

[@connyschilling4199]

God video very Lerning detail video.

[@wutang_bing8090]

Really wish you could do another restoration with some step step commentary But I’ll definitely be using these videos to rebuild a 97 targa lx I just picked up

[@Tomology]

Hope it helps you out! I am not planning on doing step by step commentary videos.

[@backcornerparts5408]

Jelmer beunhaas mooi project man

[@danijuggernaut]

Cool, i did the same job in June. 74cc Airsal reworked on a Puch 4v. Allways check the cylinder piston kit like you did. Nothing is good by deeper checking. The Airsal did not open fully the transfers with the supplied base gasket. The exhaust timing was only 175° (just ridiculous). By grinding the exhaust port 1mm for longer opening time and cutting 2mm the piston back for longer admission time. I have now, 185° exhaust time, 175° intake time. This timing is for high rpm and works only excellent beyond 8500 revs up. Listen my dear friend, you did a too small piston ring gap. A too small gap is the reason of the most seized total failure of the piston. 0,15mm is far too small!!! The rule says that the gap should be 0,089mm for each 10mm piston diameter. Your gap for 70cc should be about 0,3 to 0,35. I have on mine 0,41mm. 70cc is not a joke, more power, more heat, the most common failure is that the piston rings touch by heat dilatation and the engine gets seized. Another question to you: Have you checked first the timing before you started machinig the cylinder? You should first check transfer opening and choose the right base gasket in thickness. From there on, protractor and check. Another thing to blame on Airsal, the supplied gasket where worthless (0,3mm base, 0,6mm head). Now it´s excellent, i have 0,5mm base gasket and a 0,4mm head gasket and so, a 0,8mm squish.

[@Tomology]

Thanks! For the ring gap I used a general rule of bore diameter *0.004mm. I don't have a 0.18mm feeler gauge so I made sure the 0.15mm fit easily and the 0.20mm fit tight. I think 0.41mm ring gap for this 70cc is too much and will cause excessive blow by. Yes, I checked the timing before I started machining the cylinder. I also have the experience that generally the supplied base gaskets are incorrect. Good to check them too.

[@danijuggernaut]

@@Tomology Yeah man, they lie to us. All tuning manufacturers. 0,4 is good for my 74cc. Your 70cc need at least 0,3mm. Believe me, don't destroy your engine. Drive aircooled cylinders have big tolerances and a little performance is sacrified due to this generous gaps and tolerances. In the other hand, they are indestructible tough. Mi Airsal pistonring came with 0,25mm. Not acceptable in my hot mediterránea weather. Believe me, 0,3 gap. I screwed my baby Up to 15000 rpm and no overhead issue. Just thing, you will have to open your engine frequently for inspection, quick you will detect any failure before total breakdown. Cool Cranckshaft bearings, they look solit. Puch L17 are not so good, serious worn out above 13000 revs. Cheers mate enjoy your Moped.

[@spotter3970]

​​​@@Tomologyi use 0,30-0,40 on 70ccm LC .... your 0,15 will be burn change pls :) nice Video good work

[@user-ir4yf8ci8e]

6:23 когда я вижу эпоксидку на металле, да ещё в ДВС, у меня сразу начинается изжога☺

[@Tomology]

Metal epoxy works amazing for this application!

[@bulasturubula3660]

I'm sure this thing would smoke my 650cc all day long xD

[@Tomology]

I don't know about that ;)

[@chaneldadakan2057]

Saya sangat menikmati cara pekerjaan anda..👍👍👍👍👍😚😚

[@user-vd9jx1kt8u]

Im watching this working on 3 tomos at the same time cool video i fix and sell hit me up they are 1999 targa,tagralx pedal & none pedal.

[@derekhamlin4871]

When fitting piston rings you only need to file and deburr one side of the piston ring.

[@mustfindaway]

Nice :D

[@gabrielcarrizo581]

ME ENCANTA

[@managerslovenia2839]

frcomoto clutch best clutch ever , one series is have a thick lining i get this too , but next series are perfect

[@tomoshop]

😍

[@harrygroen69]

Hele leuke video! in mijn jonge jaren aardig wat tomosjes omgebouwd de meest gruwelijke was een s-25 1 speed met een 65cc airsal hd kop en 15-15 carb dat ding vrat koppelingen en heeft heel het frame, achterbrug en achteras kromgetrokken

[@Niels-booij]

met een airsal 65 en 15mm? zat je frame al vol scheuren ofzo 😂

[@harrygroen69]

@@Niels-booij nee, ik kan snel materiaal bouwen en ook weer slopen 😂

[@fereza98]

good job man👍🏻, what dremels do you use?

[@Tomology]

thanks! I use non ferro burr bits

[@Joschi746]

That built is so fuking nice !❤

[@Tomology]

thanks!

[@leonardaardenburg8985]

Super filmpje weer, welke dremel frees set gebruik je? ga zo door!

[@Tomology]

thanks! ik gebruik relatief goedkope non ferro metaal freesjes

[@timbeldman3165]

Leuke video! Welke items gebruik jij bij het (de)monteren van de lagers? Heb dit namelijk nog niet eerder gedaan en ben van plan om deze binnenkort evt te vervangen

[@Tomology]

een heatgun en freezespray voor het monteren en een binnenlagertrekker voor het demonteren

[@skutertuner5518]

SMETI !

[@tttrrriiipppyyy]

Hey. At 6:49 is it worth shaving the piston at the bottom to match the port? or is it best to leave it as is? Great videos by the way. Not enough content like this on youtube for Tomos people. Cheers from Liverpool UK x

[@Tomology]

I haven't done it, but I've seen tuners do it. Probably it's worth doing it. Thanks! Love that you enjoy it.

[@tttrrriiipppyyy]

@@Tomology my parmakit cylinder arrived today and i honestly thought i would have enough metarial on the a55/a52 case to open up the transfers without jb weld . I was sadly wrong :( i'm a little scared to use jb weld .. Which type did you use for this ? Did it hold up well and not fall off ? I'm also thinking of just sticking the cylinder on as is but then the potential gains of having the huge transfers matched would be amazing .

[@Tomology]

@@tttrrriiipppyyy Yes you need to weld or epoxy extra material to the cases. Use original JB Weld. I've used it before on my blue cafe racer and many other people used it without any issues. Good luck with your Parmakit project!

[@normanwray1341]

You a fit body parts, do you fit motorized bicycle carburetor?

[@Tomology]

it's a 19mm dellorto phbg carb

[@blochi.official145]

How much mass did you use to expand the engine block? (6:18)

[@Tomology]

I don't know the exact amount in grams. I made sure it's a few mm thicker around the ports and base.

[@reufhamzic4979]

Can i install a 70cc kit on my Tomos Automatic A3L with a stock 50cc head?

[@johnnykjaersgaard7978]

What epoxy did you use to add material to the case?

[@Tomology]

JB Weld

[@xBorisD]

Would a kit like this fit on an apn4? I am very interested into upgrading to 70cc but I don't wanna buy something just to find out it doesn't fit

[@Tomology]

Yes it would. All a35 kits do fit on an apn engine. But the transfer ports are different so that needs work. Also the fitment of the intake and exhaust ports might be different. It won't be plug and play.

[@zakka7973]

Great video. What’s the cost of parts for this build please.

[@Tomology]

Visit Tomoshop.nl via the part links in the description and you will have a rough estimate.

[@incomplete628]

Whats the fuel/oil mixing ratio on this 2 stroke motor?

[@Tomology]

1:50

[@dietznutz1]

​@@Tomology😂 imagine that

[@markovideski9401]

How fast dose it go

[@Joschi746]

Which exhaust can i drove on this cylinder?

[@Tomology]

You can install different exhausts which are made for 70cc kits

[@harijurada6058]

Does this KIT fits on ATX engine? In Slovenia and Croatia, we do not have, possibility to by any KITs!

[@Tomology]

I believe it does fit. I can fit a35 cylinders on a 4L engine which is basically the same as an Atx engine. You may have to adjust the intake and exhaust fitment.

[@harijurada6058]

I know that. In the 90. we had possibility to tune our Tomos, wiht parts from Italy. Golden times. From whitsh country are you from? And happy 2024!

[@Tomology]

@@harijurada6058 You too! I'm from the Netherlands

[@nixcc1628]

A question, why did you choose a parmakit cylinder, aren't they notoriously bad?

[@Tomology]

They do not have the best reputation indeed... Really wanted to see for myself, learn why and see how it performs with some adjustments.

[@nixcc1628]

@@Tomology Nice, how was it?

[@Tomology]

@@nixcc1628 I haven't been able to test it yet.

[@rwtuning_0487]

zet er een polini big valve kit op groot verschill in vermogen

[@Tomology]

klinkt als een idee!

[@rwtuning_0487]

@@Tomology werkt er goed heb hem zelf ook op een zeer snelle setup en loopt aardig rap

[@robertchaplow]

Where do you get your parts?

[@Tomology]

tomoshop.nl!

[@sin420hova]

I need help with my moped

[@Tomology]

What's the issue?

[@sin420hova]

@@Tomology My dad commented This💀Idk what he needs

[@joergmeinke2956]

Jörg Meinke kann kein Englisch nur Deutsch habe es vergessen zu sagen.

[@Joschi746]

Ah okay jörg 😂😂

[@brainworld]

у нас такие изредка попадаются а с ручными коробками не найти

[@nitrorccar9990]

Wat voor sproeier zit er in?

[@Tomology]

Voor de test stationair 50 en hoofdsproeier 105. Het zal met afstellen nog wel veranderen.

[@eriksinkefilmt8477]

Waneer komt de volgende video kan niet wachten

[@Tomology]

goed om te horen! helaas kan ik nog lastig zeggen wanneer, omdat ik nog herstellende ben van een operatie.

[@gijsgreef]

Wat zijn de afmetingen op welke plek je dat gat in de zuiger maakte

[@Tomology]

Precieze afmetingen weet ik niet. Het is vanuit de cilinder overgetrokken en op grootte gemaakt zodat de inlaat 360 graden open is.

[@Timdiephuis]

wat is dat grijze spul wat je gebruikt voor bij het blok en de ontstekingkap

[@Tomology]

Dat is jb weld metaalepoxy

[@Timdiephuis]

kan je dat oom bij tomosshop halen @@Tomology

[@marshallkaufman3123]

i have a Tomos mc80 dirt bike the engine looks really similar to a a35, its needs a rebuild. does anyone know if i can just buy a big bore kit for the a35 engine and put it on. there is not much information on them online either.

[@Tomology]

Hey man! By comparing pictures of a 74cc puch/tomos cylinder and the mc80 cylinder (both have a bore diameter of 47mm), you can see that the width between the cylinder studs is different. The studs from the mc80 seem a bit wider spaced, so I guess you can't put an a35 cilinder on it. I'm not 100% sure though. Maybe someone can confirm it for you!

[@marshallkaufman3123]

@@Tomology thank you for explaining. there is very little information about the Tomos mc80 on the internet (guessing they didn't make too many) so i the more i know the better!

[@florisvanvliet8607]

Wat voor afplaktape wordt er eigenlijk in de video gebruikt?

[@Tomology]

Die oranje schilderstape is bij de Action verkrijgbaar! Ik vind het zelf een fijne tape.

[@florisvanvliet8607]

​@@TomologyThx!!

[@nickski]

Do you have the part # from mvt for that cdi?

[@Tomology]

MVT-RJ34-61

[@nickski]

@@Tomology Thanks!

[@Tomology]

@@nickski check the link in the description!

[@nickski]

@@Tomology I saw that but I am trying to find it here in the states. The part # on tomoshop doesn't match anything I can find

[@Tomology]

@@nickski I get it. I don't know the manufacturer part # of the mvt dd kit, but I do know tomoshop ships to the usa too. The cdi part # I found with google search.

[@derkmateman2152]

Welke epoxy gebruik jij

[@Tomology]

jb weld

[@christianvlogs8277]

Wich color is going on the tomos

[@Tomology]

bright orange a bit like the mvt ignition

[@christianvlogs8277]

@@Tomology nicee

[@tangoalpha8381]

🏆🏆🏆🇧🇷🇧🇷🇧🇷

[@derkmateman2152]

Welke dremel gebruikt u

[@Tomology]

Een dremel 3000

[@Samjuurlink]

6:20 is gewoon twee componentenlijm voor metaal toch?

[@Tomology]

Ja. JB weld gebruik ik

[@Samjuurlink]

@@Tomology Top! Dankjewel.

[@gamiwv]

Everything is very nice except from the driving toothwheel of the final transmition. I don't like to destroying the cases of the motor

[@Tomology]

Thanks. The cases are not destroyed though. They are modified to fit the part.

[@gamiwv]

@@Tomology 😅😅😅😅😅😂

[@steverandall5814]

Please be careful! Petrol is indeed a wonderful cleaning and degreasing agent, but it is also very dangerous to use for this purpose. Here in the USA, if the Occupational Safety and Health Administration caught a shop using petrol as a cleaning/degreasing agent in an open container such as you were using, that shop would face a very, very large (tens of thousands of dollars for the first occurrence) fine, especially if it was being used indoors.

[@mopadrider6012]

Luckly this whas filmed add home and in europe probably even my own country because there are lots of tomos here in the netherlands

[@bortchy]

It is slovenian company

[@goranpetrovic1714]

RESPECT👍🔧🔩🛠❤

[@BrendaEM]

Please don't drill toward your hand. My old boss told me about the person who was drilling a car wheel-well, when the drill went right through...his hand. He went on to mention all the meat caught in the flutes. For decking the block, a piece of glass such as tempered glass from an old scanner makes a nice makeshift surface plate. If you wet the sandpaper, it will stick like magic. A drop of dish-soap makes it slide nice, well nicer, anyway. Also the water keeps the sandpaper clean.

[@peraz968]

24:40 Your engine is running dangerously lean. Put bigger nozzles to the carb. And thanks for the video, nice work dude!

[@Tomology]

thanks! it was the first start. jetting might be off and maybe there's a leak somewhere. have to test it soon when I have the frame done!

[@benjamindivjak1950]

@@Tomologyand why did you sanded a little bit between piston rings??

[@edboer2851]

​@@Tomologyik moest dit spruitstuk ook vlakken voordat hij niet meer lekte. Was waarschijnlijk kromgetrokken door het lassen. Maar beter haal je een spruitstuk met een betere flow. Deze zijn een drama. Ik heb in de hoeken kneedbaar staal gedaan om de flow te verbeteren. Dat scheelde wel maar het is niet optimaal. Wel weer heel netjes gemaakt dit blok👍

[@Tomology]

@@benjamindivjak1950 to get the right ring gap. the metal ring expands when heated and then the ring will create excessive friction if the gap is too small which could cause catastrophic damage. with the right ring clearance the engine will run fine. too big of a gap will cause excessive blow-by of the gasses inside the cylinder.

[@Tomology]

@@edboer2851 dankje! goed om te weten van het eventuele kromtrekken. ik heb voor deze gekozen, omdat hij dan mooi zijdelings langs de tomos loopt net als het origineel. flow zal inderdaad niet top zijn op deze manier.

[@danvilladsen8911]

never use copper paste on aluminum. the copper will erode the aluminum

[@Tomology]

what do you recommend as a replacement?

[@samuelmartin2680]

Attend mec t'es français ou anglais ?

[@Tomology]

I'm Dutch!

[@samuelmartin2680]

@@Tomology ok tu a traduit ce que j'ai écrit ?

[@FMJ_Plumboy]

2 strokes are supposed to smoke, that gas is to yellow.

[@Tomology]

it's mixed with yellow 2 stroke oil at a 1:50 rate

[@yeetreeves6832]

Tomos is een beetje roestig denk ik😂

[@Tomology]

Gaan we verandering in brengen!

[@benweissman4410]

Poor cases

[@alanpo4373]

Ako nekome trebaju tockovi (oba) za automatika sa gumama neka se javi,prodajem ih...

[@WokeYtube]

your tyre is off center 😃😃😃

[@Tomology]

yes, it's a flat tire. I bought the moped like that

[@WokeYtube]

Then police notice you driving 70-80km/h and take away your bike.. What is the point ?? And what is not good is that 70cc engine can cool enaugh with air so it wont last.. Nice video all together

[@Tomology]

thanks, it's fun! and if you register it as a motorcycle there won't be a problem with speed. air cooled works fine when tuned properly. lots of 70cc+ mopeds are air cooled too!

[@WokeYtube]

@@Tomology if you register as motorcyckle ??? Wthf yoi cant change homologation yourself !! That tiny bike have no tyers to support the speed, no brakes ets. Its not that simple. Its easier to buy bigger bike bro

[@Tomology]

@@WokeYtube no, I can't. but officials can. it has been done before in the Netherlands with different kinds of mopeds. the tyres are highway rated to a max speed of 150kmh. the brakes need to have a certain braking distance.

[@WokeYtube]

@@Tomology I dont belive that this can be made legaly, no chance and if it can than cost of it all will just surpass buying of second hand motorcykle.. And of course you didnt mention that you need big A driving licence for what you make.. Its pointless , compleatly..

[@Tomology]

@@WokeYtube well, make sure to subscribe cause I will do it one day! if you think it's pointless, I'm okay with that. I think it's fun!

[@user-xb7yt1eb6b]

Where did you bought the clutch assembly?

[@Tomology]

All parts used in the video are from Tomoshop!