Ready For performance!

[rogergendron1]

OK thanks for reply. Sorry I haven't been on the forums much. Been busy with work. But I'll have a new dax bottom end coming in the mail in a week I hope and a free wheel and sprocket adapter. I think my coaster brake wheel bursted. So it will need replacing. Also I dida mild porting on the cylinder intake and exhaust. and still waiting on that hi comp head from you roger.

i heard you had a problem with your motor and tore it down right ??? i held off on sending it .... its siting right on my coffie table ready to go right in front of me with a champion plug spare gaskets for intake and exhaust, a larger 1.6 mm head gasket incase your comp is too high for street use or you dont want to run 93 oct you can add .6 mm to the deck hight with the gasket and run 89, and stainless steel 13mm nuts and lock washers all packed up in a box .

i am looking at it right now .... will send it tomorrrow srs this time its ready to go and i am sick of looking at thee box lol your prob wondering what the heck !!!! dont worry lol it yours you got it i judt slacked on sending it when i heard you blew your top end .. sorry man its going out tomorrow promise !!!

 

[rogergendron1]

Ok i have a list of orders i've made for my Improved motorized bicycle.

Brakes with lever.
Dax bottom end.
new carb with jets.
felt motor mount.
41t rear sprocket.
expansion chamber.
and more coming. will keep you guys updated.
Oh i also have a new bike.

great choise on the 41 t sprocket !!!!!! i believe 39 to 41 is the perfect size for all around power and speed ! you wont be sorry with ts build man i will tell you that !!!

dax balanced motor
port and polish
better carb and manifold
tunned exhaust and x chamber
high comp 12:1

your heading tords a pefect street rod build !!!!!

 

[Nooflyer]

Thanks @roger, i wouldn't mind using higher octane if need be.

My top end is fine i just broke a motor mount stud because the rear sprocket bearing exploded. I also received my package from thatsdax and everything looks good but i never got the head stud bolts for the bottom end. Anyway i emailed dax to see if it was included (i spent almost $200) hopefully it is. Turns out the studs should be M8x1.25x114mm and i couldn't find them at my hardware store.
Anyway, I just finished port matching my expansion chamber and intake/exhaust port on the cylinder and i think its a winner. Also scuffed up the intake manifold for better mixture (atomization?) Not sure if my del'lorto clone will work better than my NT carb because there might be a gas leak from one of the gaskets.
If i can seal it better then that would be superb because i have 5 M5 jets for it.
Enough talking here's a pic.

 

[Nooflyer]

a better look at my intake manifold!

 

[48ccbiker]

those banana pipes are horrible.
basically they have no normal header length which throws the wave timing off sync with the engine.

 

[Nooflyer]

@48ccbiker so would it be better to just use my stock port matched muffler?

 

[rogergendron1]

@48ccbiker so would it be better to just use my stock port matched muffler?

no no no.... what he is saing is that the x chamber has no header making the power band too high, what you want to do is cut your stock muffler off at the weld where it atatches to the cat then cut the flange off the x chamber and weld it to your stock headder tube .

this will give you a headder length that is close to correct and an x chamber that will work out pretty good at the right spot.

with the length and diamiter of the stock eadder tube added to the bananna chamber it will put the power band lower where you can actualy use it . you may also want to drill out the stng er pipe to at least 5/8 in that seems to be the minimum needed for high unrestricted flow.

if you cant weld just cut everything yourself and bring it to a muff shop and have them weld it for a few bucks.

cut the stock muff off the headder
cut the flange off the bannana pipe
weld together
port match
assemble

ohh and you did well with the port matching of the intake given what you had to work with . good job

if you use the stock headder tube and weld the x chamber on you should be left with something like pic #2

the x chamber in pic 1 has way too high of a power band but is a very good and useable designe it just needs some length of tube added to it

 

[Nooflyer]

Ok thanks roger again!

I think there is a nearby auto shop that can help me out.
Til then i've kind of mocked up what my bike will some what look like assembled!
pics will come soon

 

[Nooflyer]

A quick teaser but something is still missing!

 

[Nooflyer]

Good think i decided to buy a dremel! Now 40% complete!

 

[rogergendron1]

Good think i decided to buy a dremel! Now 40% complete!

excelent work !!! and wow nice bike i am digging the front forks !!!

now all you need to do is weld the x chamber on the header tube and install the high comp headd thats on the way !!!

you realy do need a dremal to get the most from a china girl, the intake can be ported as far as you can take it on the bottom and widened as far as you can go on each side but only clean up the top dont take any off. the exhaust port can be raised as far as you can take it and the same with the sides but leave the bottom alone only clean it up. the ports should be D shapped, gring the intake down in a D shape and exhaust up in a D shape. the intake port the D should face down and the exhaust port the D should face up. then port maatch everything and grind ramps in your piston, then trim the skirt so it does not block the intake port, i just cut 1/4 in of the whole intake side to lighten it., and mine takes a whole lot of abuse !

with those mods you should be running a motor that feels like its done ! you wont need or want to upgrade anything else lol it will have the power you want !

 

[rogergendron1]

ohh and that intake manifold.... port the inside of it so the angle part does not have a sharp edge , round it out as best as you can so the fuel can flow by it easyer. angles like that cause turbulance and squeeze off the flow, rounding it out will open up the diamiter and help out flow. also port matching it at the jug will help too

 

[Nooflyer]

Thanks I like the quick replies.
I believe I already trim my piston intake skirt about 2-3mm already but have touched the top.
As soon as i get off work then ill mess with the intake some more.
I already made port match intake gasket out of the gasket paper i had.
Will keep you guys posted.

 

[Nooflyer]

Ok i've gotten a little done today on my motorized bicycle.
I loosen the drive chain because it was really tight and i didnt want to risk it snapping and smacking me in the leg, i also installed the chain tensioner for good sakes.
I also installed the cdi and throttle/kill switch. soon i'll solder the wires for safety.
Should i solder the kill switch wires also or just the motor and the cdi wires?

 

[Nooflyer]

Ok got a little carried away but made more progress.
I got my head bolts from thatsdax which shipped really fast.
Installed the head fixed the sprocket and chain again. Got bored/creative and wrapped my handlebars with electrical tape and i like it. Anyway here's another snapshot.

 

[rogergendron1]

looking great so far ! i am impressed !

the head i sent you should have been delivered this morning .

if you can or are willing try and take a pic of the dax head and the one i sent you side by side i would like to see combustion chambers to do a quick visual comparison of the 2.

the one i sent you has a flat squish, typical of flat head 4 strokes but seemed to work realy well for top end speed, also i know the chamber volume is 6cc average measurement so it is easy to calculate comp should be 12:1 or verry close. not shure of the chamber volume of the dax head but looks to be nearer to 7 or 7.5cc somewhere around 10.5 to 11:1 comp .

the dax head will certainly offer you a bit more power everywhere but the one i sent you is chambered and milled for top end speed and power.

i also sent you 1.6mm gasket paper with traced head gaskets on it so you can make a larger gasket to play around with compression ratios. if you use the suplied 1.6mm gasket you will add .6mm to the deck hight and lower comp a little . the head i sent you has had its gasket surface decked perfectly flat so you can run it with no gasket if you like, this will net you more comp that even using a single stock gasket ! it would be like taking 1mm off the already decked head !

 

[rogergendron1]

all you need now is to measure the header length for your desired band and have a shop weld the x chamber on at a good angle and your in buisness !

 

[Nooflyer]

Sounds good roger! I will take some side by side pic comparisons also.

Antother question about your previous post talking about the d shaped exhaust/ intake ports. Is there a picture showing how the ports are? I completely understand what you mean by having the ex port in the shape of a D but facing up and int port facing down, But i just a fan of pictures. lol I'm more of a visual learner!

 

[Nooflyer]

Wow I'm excited about this bike already. Before this build i was leaning towards a 4 stroke engine no i have no regrets by getting another HT engine.

@roger
I received you head/bolts and lock washers ( I can not thank you enough)
and i also took pics for a little comparison.
But since i bought a new bottom end from Dax (even though the top end is used) i feel like i should break in the engine first before swapping over your head. Also that thicker head gasket did the magic. I was a little skeptical about using regular gasket material for the head but it works. I'm wanting to try just two copper head gaskets next time though.

The stock head gasket didn't for either head as the compression was too high! I only weigh 160lbs and the back tire would just skid without any roll. so i placed rogers thicker gasket (.6mm thicker than stock) and it started first try.

After it started i let it run for a couple of minutes to warm up. I then took it to the gas station just to see the get up. It seems like it's gonna be a beast.
But i did not exceed 15mph. I'll wait until the first couple of tanks then i'll post progress and top speed with the 41t and port work.

I feel like i've built Frankenstein. Can't wait til next ride! Thanks. Will update sooner than later.

p.s. that banana pipe actually sounds like a 2 stroke. I can't imagine how the SBP pipe would sound on my bike.

 

[rogergendron1]

the dax head has a nice band and judging by the thickness of the gasket surface base probably a lot lowwer comp than the one i decked, it has almost zero suface left were as the dax is almost 1/4in thick. i would definantly runn the dax head for break in and with the thicker gasket break in will be less harsh on your motor . once its broke in and tunned up switch out to a thinner gasket for more comp and see how she goes, want even more comp ? swap heads lol you have pleanty of options now for various comp ratios !

there is a plug i cut for clearance if you had piston issues but if you dont need it toss it out . i ran it for a day to make shure it worked and it did, but i would run a normal plug at all times if possable that type of modded plug is strictly for special apps where a reg plug can not be used

that gasket material is not regular lol its verry high heat and rubberized. it will withstand high compression, gass, and high heat . expensive stuff lol metal gaskets are better though technicaly speeking anealed copper