roto start options for T-Maxx 2.5 in preperation for build

[johnfm3]

I have gotten my first t-maxx with a 2.5 engine an EZ Start.

My long term goal is to build a tubed chassis to house a twin 2.5 engine setup. With that in mind, I am finding (based on other threads an youtube videos) that roto start is the easiest to work around with the shock towers, exhaust, an such.

My question. Which back plate options do I have? I have not pulled the engine out as of yet. I have seen some starting plates only use 3 of 4 bolt locations. Are the bolt holes symetrical? Can that starting plate be rotated in all 4 optional directions?

As of now, I am leaning towards OFNA for my parts as they have a back plate which allows the rod to goto the 9 oclock location an make use of all 4 back plate bolt holes (But unsure of the fitment). Any one have any experiance with this?

Thanks,
John

[Nitronaught]

The bolt holes ARE symmetrical. But there are 2 cutouts on the backplate that must face the top to allow proper fuel flow, I mistakenly put mine on incorrectly and had a lot of fun trying to get it to run... Needless to say, I found out the hard way.

[johnfm3]

The bolt holes ARE symmetrical. But there are 2 cutouts on the backplate that must face the top to allow proper fuel flow, I mistakenly put mine on incorrectly and had a lot of fun trying to get it to run... Needless to say, I found out the hard way.

Interesting. Am I to gather from your comment that Nitro engines use the fuel to lubricate the starting system as well?

Do anyone have any images?

The thought I had was left engine would have the starting wand to be pointing to the left, an the right engine would be pointing to the right. Or see if I can install the back plates so that the wands are pointing towards the middle of the RC. Again, this is with little experiance. An so my research begins.

John

[Nitronaught]

Sort of...

At the back of the crank a plate with a shaft goes on, the plate and shaft go through the backplpate. After the backplate (remember cutouts to the top) there is a shaft that a one way bearing/roller clutch goes over and rides on that shaft, the starting mechanism sits on top of that, a pull/recoil start or EZ start fits over it...

This is what the starter shaft looks like with the backplate on.

The one on the left is a Pro 15 engine the one on the right is the 3.3

[johnfm3]

Ok, so the back plate gets installed. Then the casing which holds the starting system (pull cord or gears) bolts to the back plate. In your image, the one on the right (the 3.3) has a square back plate. From that point it would look like to me that the starter case can go on in any of the 4 options (assuming those out bolt holes are equal). Also assuming the starter case bolt pattern match.

Doing more digging, I see that the OFNA has a small side gear which rotates the main gear on the crank shaft. But I have another option. Looks as if the Losi one allows the starter (or drill) to turn the crank directly or pull start.

Any ideas if the Losi one will work? Are there any good write ups on this topic?

John

[johnfm3]

Bump....

Any suggestion about roto start options such as losi or ofna.

John

[ajcar]

i had a roto start for my t-maxx back in the day. it was called a tiger drive. got it on ebay. it uses a strait hex rod with any high speed drill.
this is what im talking about
http://www.ebay.com/itm/Sullivan-Tig...item2ec53a6c12
a long allen wrench with the bend cut off works.

[johnfm3]

I am liking what I am seeing with the sullivan 682. Thanks for the suggestion.

John