Bw'S ( Zuma) 100cc and Jog MVT SC90

[90GTVert]

Looks like it will be a strong runner!

[moofus02]

I might of missed it but what is the bore and stroke of this new monster?

Sent from my PG86100 using proboards

[kevin55950]

Bore: 50,6mm
Stroke: 44,8mm

[kevin55950]

Now looking for the good exhaust, I'll only go drag racing with the MVT so I'll pick the MVT exhaust and if it's too loud, I'll look for a longer silencer, I'll keep the 100cc for the street. The MVT exhaust is kinda hard to get, because it will cost a lot of shipping at one place, take a month at the other, not available for the 90 at the third...

[kevin55950]

I should make a port map of this engine... ports layout is very interesting.

[kevin55950]

Cyl. head seems to have no cooling near the spark plug... any recommendation ?



MVT sells an aftermarket head but the head costs 80-100 euro plus shipping, which is a two-part head, not single part like this one.

[teddy554]

The exhaust port on that cylinder looks huge would love to see a port map of it

[kevin55950]

I'm not used to do port maps ... I'll try to do one!

[kevin55950]

Today's work:
-took out the case from the Zuma
-splitted the case
-took out the crankshaft and bearings
-started to mod the case:


Made a passageway for the connecting rod.





Trench cut case mod.

to-do list for the weekend (between 12hrs work day):
-align cylinder's port on the cases
-do the 2nd half of the case
-clean and prepare the case for epoxy.
-find a good epoxy for the case (JB weld is far from the best IMO and it's the only one I'm able to find...)

[190mech]

Metalset A4;
www.skygeek.com/a4-11oz.html?utm_source=googlebase&utm_medium=shoppingengine&utm_content=a4-11oz&utm_campaign=froogle&gclid=CJn7zcTL6rYCFUJa4Aod7zQAgg

Devcon F;
www.amazon.com/Aluminum-Putty-lb-PRICE-BOTTLE/dp/B000HZOE82

Epoxy should go on before cutting cases..Clean and sandblast back side of cases before epoxy application..Tape over the holes and apply a 6mm thick coat on the back side..

[kevin55950]

The Devcon price is great , but I don't think I can buy it from Amazon.com and there is no one on Amazon.ca ...
Shipping is pretty expensive for the metalset. Is the metalset thinner ( more ''liquid'') than the Devcon?
I have no problem to pay for a good epoxy, It's the customs that I'm afraid. They might be classed as ''dangerous goods'' and I'll loose the money I've put for the epoxy if they don't let it pass.

[kevin55950]

I finally found somewhere I can get Devcon F, I'll recieve it in a week or so.

[190mech]

COOL!Glad you found it..Devcon F is THE best epoxy for our applications!!

[kevin55950]

I'll also need a ''reverse'' intake and manifold spacer. At the price they're sold, and with the time I have, I'll try to make one. I heard Teflon is a good material for this application, I have some left I'll cut some rectangle- shaped Teflon plates ( 3 or 4, 3,33mm each) and glue them together with epoxy. Then, I'll drill the holes for the screws and split it in half with an angle in the middle to make the reedblock seat higher with a certain angle to make it face more toward the cyl. ports.
So I'll have a reedblock spacer and an intake. I'll cut the inner part of the reed spacer to fit the vForce3 reeds and for the top part I'll look to glue (with epoxy) a PVC tube where I can fit a rubber intake boot.

If I don't need them on my atv, I have 2 Koso 34mm copies ( Koso on 1 side, Sunworld on the other with round main jets and ''4 stroke'' nozzles). I may use one on this build, mvt used a 30mm carb on their dragster.

[kevin55950]

Sandblast gun will arrive tomorrow. My dad is a professional painter/sandblaster but I'll have to sandblast the cases before epoxy and maybe after to get a good finish. Instead of taking the case to his shop every time I need sandblast to be done, it's better to have it on hand.