New guy here... Morgan-esque 3 wheeler

[landuse]

Please use the edit button at the bottom right of your posts. This will save you from double posting minutes apart

 

[OzFab]

What are the thoughts on this? 10" rear wheel......
http://dallas.craigslist.org/ndf/tag/4196010614.html

These look to be the specs.....
http://www.rcramer.com/bikes/pr200/drivetrain.shtml

Appears to be 10" tyres on 4" rims.

I'm surprised no one has suggested a rear pitbike wheel or, if that's too big, a rear wheel from the pocket bike version...

 

[itsid]

The gearing appears too low, but could it be multiplied with a home-made jackshaft...... couple bearings, a rod, and 2 more gears......

A few words of warning:
correct, you could never fit 9:1 ratio without a jackshaft or a much more expensive gear reduction box.
So go for a jackshaft.

Do not underestimate the weight of your finished three wheeler.
Do not use either #25 chain OR pocketbike wheels.
both are not up for the task.
you'll save maybe 10 bucks and you'll end up buying a new set of sprockets and chain and a new rear wheel in less than a month of driving (spending another 60 or something)

a smaller rear wheel isn't going to be neccessarily cheaper (incl body and stuff), check that first!
think about where you put your engine, draw your scale plans and see what room you have for a wheel.
I assume wou'll end up with rear end of about 20" for example.

Don't forget that you will need to fit a person inside; and even kids have legs; so be careful not to get too small.

'sid

 

[OzFab]

Do not use either #25 chain OR pocketbike wheels.
both are not up for the task.

I'm not too sure about that; pocket bikes are around 5-6hp so, using a 2.5hp, I think they'll be ok...

Everything else,

 

[itsid]

I'm not too sure about that; pocket bikes are around 5-6hp so, using a 2.5hp, I think they'll be ok...

Yes but they're also 6 lbs of weight so let's say 100 less than a kart;
I think the additional inertia is what will cause problems and failure.

I'm not entirely sure because there are more factors to count in,
but let's just put it this way:
it'd be safer to use kart parts than pocket bike parts at least.

'sid

PS Please, do not use pocket bike brakes at least, if they fail you will get hurt!

 

[firemanjim]

Appears to be 10" tyres on 4" rims.

I'm surprised no one has suggested a rear pitbike wheel or, if that's too big, a rear wheel from the pocket bike version...

I did suggest that in post #36..... The mini crotch rocket i have has a rear tire i think would be perfect for his intentions and still a good size for the bmx tires. Its raining now,but ill post a pic and size shortly. It uses a #40 but you could easily modify a big diameter #35 sprocket..... to get to 9:1 with no jackshaft....

 

[OzFab]

Yes but they're also 6 lbs of weight so let's say 100 less than a kart;
I think the additional inertia is what will cause problems and failure.

I'm not entirely sure because there are more factors to count in,
but let's just put it this way:
it'd be safer to use kart parts than pocket bike parts at least.

'sid

Fair point

PS Please, do not use pocket bike brakes at least, if they fail you will get hurt!

They're nowhere near strong enough

I did suggest that in post #36.....

Although I did see that, I thought you may have been referring to the mini moto style bike, I was simply clarifying more towards the dirt bike style bike

To go one step further, something like this:

 

[sxk122]

with a transmission ratio of 9:1 (jackshaft set up: 12->27-10->40 )

I'm a bit lost here.

If I follow you, the engine would have a 12 tooth centrifugal clutch leading to a shaft with a 12 tooth gear on one side, powering a 10 tooth gear leading to a 40 tooth gear on the wheel?

 

[itsid]

I'm a bit lost here.

If I follow you, the engine would have a 12 tooth centrifugal clutch leading to a shaft with a 27 tooth gear on one side, powering a 10 tooth gear leading to a 40 tooth gear on the wheel?

^^ I fixed that, but yes;
clutch has 12 teeth, the jackshaft (input side) 27 leading to a 10 tooth output and to a 40T axle(or wheel in your case) sprocket from there; exactly

'sid

 

[sxk122]

is there a table for figuring this out? i'm not sure what to search for, maybe you can help direct me...

Looking at 5/8" bore clutches, the 10/11 tooth variations are more plentifull( and cheaper)

http://www.ebay.com/itm/GO-KART-MIN...her_Vehicle_Parts&vxp=mtr&hash=item53fe5f202c


If I used an 11t clutch, how would that affect the other numbers? If I can use a clutch in that price range I'd be a lot happier....



Someone commented on this being 4/5 scale and close to 300 lbs..... I really hope to make this a bit smaller and have the cart much lighter that 300 lbs. I have a couple sketches of basic frame ideas, and I think I'm leaning more toward a look similar to the red 3 wheeler I posted last night for a few reasons. The true morgan "rowboat shape" presents not only more difficulty welding, but also difficulty skinning the cart as it will be complex curves. I think I will be happier overall if instead I use build a relatively narrow rectangular box frame with minimal vertical bracing-- merely enough vertical bracing to prevent racking. I hope to skin this with either very sheet metal or more likely 1/8" Luaun (as I am better working with it and it weighs nothing). To create the skeleton for the upper body shape I will likely bend EMT into the appropriate hoops.



PS
I originally intended to have the engine rear of me.... but now as we debate jackshafts, I wonder if I shouldn't place it at the front? My only worry is the length of chain required, and the proximity of the chain to me.....

I think rear engine placement is still best......

 

[OzFab]

is there a table for figuring this out? i'm not sure what to search for, maybe you can help direct me...

If I used an 11t clutch, how would that affect the other numbers? If I can use a clutch in that price range I'd be a lot happier....

A table of jackshaft figures would be never ending so, have a play with this instead

 

[itsid]

Someone commented on this being 4/5 scale and close to 300 lbs..... I really hope to make this a bit smaller and have the cart much lighter that 300 lbs.

IF the bicycle has 16" wheels (I can only assume tit has) it'd be a 4/7th scale for a perfect front wheel match;
but make sure you still fit inside ...

...or more likely 1/8" Luaun (as I am better working with it and it weighs nothing).

WAIT WHAT?
luaun... phillipine mahogany???
"weighs nothing"..? that's hardwood! (and almost extinct; that mustn't be cheap either)

I think rear engine placement is still best......

Me too

'sid

 

[sxk122]

Thanks for the Jackshaft Calculator!

10/ 18/ 13/ 60 Gets me a 9.33 ratio. ($44+$43+$20ish) A bit more than I wanted to spend. Surely there is a cheaper way/ source......

http://www.ebay.com/itm/USA-Max-Tor...349?pt=LH_DefaultDomain_0&hash=item2c75b83c45

http://www.ebay.com/itm/5-8-35-Jack...S_Outdoor_Power_Equipment&hash=item2a336a155f

http://www.ebay.com/itm/New-35-Go-K...her_Vehicle_Parts&hash=item2ecaf982a7&vxp=mtr



Luaun plywood is plentifull here..... and cheap. A 4'x8' 1/8" sheet runs under $10.

I used 1/4" to built the skins for my cabinets out of. The 3 sliding doors conceal all my crap and keep it clean. I was sick of having dust/ sawdust over everything. Built the cabinets around the metal shelves I owned. The mobile saw station/ workbench was scratchbuilt. The Fan I rewired/ restored last year, blows harder than a modern box fan and looks cool to boot. The Ford logo was cut out of plexi on a friends CNC machine, and mounted to the oval made from MDF trimmed with a round-over router bit. Finished the floor myself when we bought the house.

I hate to buy things or pay people to do things I can do......

I do well with wood, very tempted to make this a wood Kart, lol

 

[itsid]

Luaun plywood is plentifull here..... and cheap. A 4'x8' 1/8" sheet runs under $10.

Ah that cheap "not even closely related to mahogany" plywood stuff...
That's only available in the US I think

As soon as we go for Lawaan (the phillipine name.. phonetically "Lauan") wood we talk about the actual mahogany trees
[Shorea contorta and Shorea negrosensis]
which is neither light nor cheap
Not even veneers are easy to get or 'affordable' in furniture quality...

Anyways.. plywood... that might work.
but please make a steel frame


'sid

[EDIT]
Oh wait.. I messed that up, didn't I?
luaun is the cheap plywood.. and lauan is the rare mahogany....
Oh you americans...
Sorry.. proceed...

 

[machinist@large]

Ah that cheap "not even closely related to mahogany" plywood stuff...
That's only available in the US I think

As soon as we go for Lawaan (the phillipine name.. phonetically "Lauan") wood we talk about the actual mahogany trees
[Shorea contorta and Shorea negrosensis]
which is neither light nor cheap
Not even veneers are easy to get or 'affordable' in furniture quality...

Anyways.. plywood... that might work.
but please make a steel frame


'sid

[EDIT]
Oh wait.. I messed that up, didn't I?
luaun is the cheap plywood.. and lauan is the rare mahogany....
Oh you americans...
Sorry.. proceed...

Some one please mark this day on the calender; WE JUST TRIPPED UP 'SID!!!! And the truly hilarious part is we didn't even set out to do so......

 

[sxk122]

Glad I could be of assistance

As far as the steel frame-- that is my intent. That said, the 4 wheeled Morgans do have Ash wood frames. Somewhat incredible.

 

[itsid]

Glad I could be of assistance

As far as the steel frame-- that is my intent. That said, the 4 wheeled Morgans do have Ash wood frames. Somewhat incredible.

the Morgan +8 does.. yes.. ever since

But honestly, that kind of engineering is far beyond DIY

'sid

 

[fowler]

2hp really isn't much to work with

As long as your happy with under 10 mph

Those box wheels proberbly won't make great front wheels

Bike wheels at all are rubbish on any vehical that doesn't lean into the corners due to there bearings

U wil also find u can't use them unless u have a mount on both sides of them

U may need to look into some sort of pedal car or existing trike to scavenge front wheels from

 

[itsid]

2hp really isn't much to work with

As long as your happy with under 10 mph

Those box wheels proberbly won't make great front wheels

Bike wheels at all are rubbish on any vehical that doesn't lean into the corners due to there bearings

U wil also find u can't use them unless u have a mount on both sides of them

U may need to look into some sort of pedal car or existing trike to scavenge front wheels from

Well, I'd put it the other way...
bike wheels are not a good idea for a 5HP engine or anything that goes well over 15 mph

Still you want to be carefull, but with that engine and the assumed speed you can get I think it's okay.

if you want to have a one side mount, take a look around for wheel chair axles and use them instead of the ones that are fitted.

'sid

 

[sxk122]

Just stopping by. Haven't made much progress. Been practicing my welds.... They are strong enough, but still less than attractive. More practice is needed..... As an aside, I did get to go out to Dallas Karting Complex on Sunday. We went out with the Miata club when they First opened in 2011, but I hadn't been back since. A buddy decided to have his birthday out there. After 3 10 minute heats I was kinda beat. My shoulders and lower back are one big bruise. Either I'm not doing something right, or the hard plastic seat doesn't like me.......

Not me, but this is the Track.

https://www.youtube.com/watch?v=ZO34Qt6qTr8