Tomos BT90 project

[pomartin]

Hello

Greetings from Slovenia
First i mus say... nice forum you got here

Let me introduce you my project

It all started when i bought tomos BT 50N and then start restoring it :





now it is waiting


than i started engine tunning
at first... two boosts


and than... 4 boosts


exhaust is 190° transfer 130°

i also made a reed-valve take-in
step 1- welding


step 2- making hole



i already enlarged the hole, so the reed valve have enought space for opening


i still have to polish it

then i bought bigger carburator- dellorto PHBH28


then one day, i was bored, and i modified serial MF3



and i allready made a plan for custom exhaust

than there was another boring day and i decided to make a plan for 6 speed gearbox
.. but 6 is too few... so i decided to make it seven
but there was some problems becouse of one screw hole, and instead of replacing the whole screw location, i desided to make 6 speed gearbox, but with gears from 2 to 7



6th and 7th gear from the secondary transmission


i also had to modify "frame" of engine to fit it in. the distance from sprocket and alluminium is 0,4 mm



than i had to amplify clutch drum


the top ring is stil under construction

than i ordered better bearings for crankshaft
FAG NJ 203 ECP


i have ordered better big-end bearing -silver cage and more needles- for connecting rod too. But i didnt get it yet, becouse tey do not sell it in our country. So i have ordered it from your country- from EMOT.nl GOD BLESS NETHERLANDS

The crankshaft still needs to be build:


there is enought material for 4 excellent and one bad crankshaft

and a difference between tomos 80-90cc original connecting rod- the gray one and the one which is made in Serbia this days.


a few things have to be done, but i must wait to get all the bearings.
18 horsepowers is expected- by calculations
i spend 1100€till now, and next week i will give the cylinder to renewal-- new nikasil--- +100€


comments and critics welcome

[MichielWolthaus]

Hmm, I've seen this Tomos already, on mopedist.si

[pomartin]

yes
i read in your topic that you have forum too, so i decided to pay a visit

[MichielWolthaus]

allright, atleast you've got an nice Tomos!
or actually you've only got nice parts

[pomartin]

hehe
soon it will be tomos

[2pac]

Oehh like like like

The bt cilinders are fast

nice ideas

I have a Tomos NTX And a bt 50 cilinder And 17,5 mm carburator

Im gone buy a 21 mm carburater and 21 mm intake

Maby you have a 21 mm bing and 21 mm intake

Here below you can see my moped

[pomartin]

i do not have bt cylinder. i have e90
that is 90ccm

and i allready saw your mopeds, and i like them a lot

[2pac]

Ha thnx on mopedist .si


I'm painting my moped when it's about 15 degrees outside.

I I have no idea which kind of color i'd paint it, do you have any suggestions?

[2pac]

Link

[pomartin]

metal-blue
for my opinion this is the best color for bt/atx/ntx models

hehe nice commercial

[2pac]

haha oke bleu metallic


there are more commercials

[drestar]

Nice

[Alex..]

nice, i'm curious about how it is going to look when it's finished

[pomartin]

update

i made holes for first two boosts (tomorow fine grinding)


and holes for second two boosts will be like that (quickly and approksimately drawed)

[Alex..]

looks nice, how come you slovenians always seem so skilled in metal-crafting

[pomartin]

hehe. everibody is
you just need some practice, and you get it throught the work you have done before

[brombertje]

looks nice, how come you slovenians always seem so skilled in metal-crafting

Maybe that's why Tomos is from Slovenia

[pomartin]

today i send cilynders, to restore


meanwhile Im waiting for parts for this project, im dealingl with this

25 kmh A35 cilinder... Im "putting" on tomos juniors portmapp.

[Fakemon]

Really an interesting project, and indeed I also wonder how come you guys always have all the tools and knowledge to tune far more better than us. Haha.

[pomartin]

actually... i worked for two years through all holidays, to get the money for the all equipment i need.
and knowledge comes through practice... ( I m doing this kind of stuff for around 5 years )

Thanks for comments