z400

iTrader: (15)

Im in the search of a few parts and some info.

i cant find crap, i've been on google for 30 minutes now "Computer anger"


what im looking for is the bearing size for both crank case bearings.
and i am also looking for the backplate to convert the engine over to bump start.



can anyone help me out?



Thanks


-Z

GenReaper

iTrader: (8)

http://www3.towerhobbies.com/cgi-bin...&I=LXHKW1&P=OW

http://www3.towerhobbies.com/cgi-bin...&I=LXCC94&P=OW

http://www3.towerhobbies.com/cgi-bin...&I=LXJPZ5&P=OW

You may want to enquire about that backing plate as it is for a TZ and if you grind the nub off your crank it may work but you need to make sure piston clearance it alright.
Pretty sure its pull start only, tho you could cheat and take the backing plate out, press or drill the brass bushing out, get it alloy welded and remachine the face where the con rod sits against.

http://www3.towerhobbies.com/cgi-bin...=OSMG2112&P=OW

z400

iTrader: (15)

i dont quite understand the 2nd part about heat pressing or something.


i understand that im going to have to do some grinding

i've got a heavily used crank im going to experiment with on grinding when i get the backplate so i dont mess up my good cranks.


im not sure if that front bearing is the right size, i may be wrong.
according to others the bearings for the trx 2.5 fit the os .18tm to

im not wanting to replace bearings with stock bearing, i'll be upgrading bearings of course.
but the rear bearing for the trx is 7 x 17 x 5

z400

iTrader: (15)

i think i understand now.


are you talking about the stock backplate?
plugging the hole or something?

GenReaper

iTrader: (8)

Front Bearing SPECS:

Outer Diameter: 19mm
Inner Diameter: 7mm
Thickness: 6mm

Rear Bearing SPECS:

Inner Diameter: 12mm
Outer Diameter: 21mm
Thickness: 5mm

Wait till some one else posts about the backing plate, i am unsure if the TZ plate is compatible so best ask some one else, i would think it would be the same if you grind the nub off the back of your crank that the rotor start shaft hooks into.

Yes i am tanking about the plugging the standard backing plate, tho you would need to make up the extra distance with alloy weld as the rotor start shaft has a thickness of about 3 mm that hooks into the crank. You would need to put a straight edge on the back of your engine blockand measure the depth from the edge of the conrod to the backing plate face and make sure that the modified plate has the same depth with no more than 1mm to spare. So the conrod doesnt fall off the crank pin. It will require some one to mill the backing plate after it is welded up and could be more cost effective to buy a TZ backing plate if it is compatible.

Ill go take a photo of one i modified myself and show you, gimme bit and ill post it up.

z400

iTrader: (15)

alright yea post some pics


im pressing out the bushing right now





Edit- bushing is out.

GenReaper

iTrader: (8)

My camera is dodgey but here you go

http://www.users.on.net/~danzig/Back%20001.jpg
http://www.users.on.net/~danzig/Back%20002.jpg
http://www.users.on.net/~danzig/Back%20003.jpg

I drilled the brass bushing out and fitted an alloy plug that i cut and ground to shape, it is pressed into the hole you drill out.

If the bush comes out you only need a plug the size of the hole or get it welded and milled down to suit.

Then on the back side i also drilled it out and pressed a core plug "Welsch plug" used in engine car blocks. I pressed that into the back side to make sure it didnt leak any air.

I know it might look rough but it lasted the life of the engine i was using till it wore out.

I had to make sure the piston would not hit the plug i made when it was it bottom dead centre and bobs your uncle.

If you are not very good at making stuff i suggest you get some one else to do it or wait to see if anyone has a better idea.

z400

iTrader: (15)

my backplate is different from yours.

i think im just gonna go ahead and buy the TZ back plate and go from there.


seems like alot of work to do what you've got done there.

GenReaper

iTrader: (8)

Yeah it is, but its amazing what you can do if you put your mind to it :]
If a TZ one is the same it would be less head butts for sure.