Columbia Tank frame bike

2 years ago I posted on here about a Felt 1903 I was going to convert.
But...
Honestly, the bike is such a work of art, I just couldn't cut into it. I enjoy it too much. Maybe way to much. I keep it indoors while the rest of my bikes sit in the garage. :whistle:

So I bought my self one of these:
<a><img src="http://i95.photobucket.com/albums/l130/geijin/Bike/columbia.jpg" border="0" alt="Photobucket"></a>

1954 Columbia, or close to that year. It looks nice but its a rust bucket, and well dented. I kind of like the rust and the dents, but I won't be ruining by putting a motor on it.

I had bought an 80cc kit from a local vedor for the Felt, but ended up robbing most of the kit parts to get a moped working (the carb in these cheap kits is supprisingly reliable, if not leaky) Enough parts were missing, and the kit used 6mm headstuds on the 80cc kit, so I found it cheaper to buy a whole new kit from Spookytooth. Besides, the new kit has a catalitic converter, so I can feel less bad about what 2 strokes to do the air :p

I do have a few questions.

Has anyone converted a tank like this to be an actual gas tank? Is it easier to just build a new tank?

Anyone use an expansion chamber exhaust on these HT motors? are they worth it?

How about these "power bottles" on the intake? do they make a measurable diffrence you can feel in the seat of your pants?

And, I know it's a noob question, but the power of Testosterone compells me.. does the Nitrous kit I've seen for the HT motors work at all?

Additionaly, anyone have any advice they want to share, or pics of similar Bikes converted, I would appriciate it.

Thanks.
 
gas tank.. never done it myself but I have seen post about people converting felts, something to think about.

the Expansion chamber is a good addition, I recommend sickbikes expansion.

You wont fell the boost bottle too much, it will make your engine run a lil smoother and for the price I fell its a worthy upgrade.

The nitrous kit, IMO, is a gimmick, there is no real way to increase gas flow to your engine, so the nitrous will just burn up your kit. Use at your own risk and post a review and pics if you do use it. Im interested.

That bike is sweet, a nice boardtrack look.
 
an expansion chamber is the easiest upgrade to get a noticable increase in power. can be a bit noisy.nitrous is for people who cant build engines!!! nice bike,very cool. :cool:
 
gas tank.. never done it myself but I have seen post about people converting felts, something to think about.

the Expansion chamber is a good addition, I recommend sickbikes expansion.

You wont fell the boost bottle too much, it will make your engine run a lil smoother and for the price I fell its a worthy upgrade.

The nitrous kit, IMO, is a gimmick, there is no real way to increase gas flow to your engine, so the nitrous will just burn up your kit. Use at your own risk and post a review and pics if you do use it. Im interested.

That bike is sweet, a nice boardtrack look.
have you ever run nitrous on anything? Seriously ive run nitrous on every vehicle ive owned (even my happytime) it doesnt increase gas flow, and what you just said makes no sense...to increase gas flow you REJET your carb.

Boost bottle WILL be felt if you do the exhaust as well. Rejet,Exhaust,boost bottle, and nitrous.then Add a 27tooth sprocket. spray at like 500rpms you'll be good.

The 27tooth sprocket will give you a loss of tq, all the supporting mods and nitrous will help regain that tq. you'll have a CRAZY bike if you do that.
 
To each their own my man, I do know a lil something about what I am talking, Ill avoid argument in favor of a peaceful thread. Nitrous is more complex then just pumping cold air in the intake... The kits are a gimmick .. I dont know what the range of the HT engine is but I think 500 is on the low side.
 
umm...nitrous isnt just "cold air". nitrous splits into oxygen and nitrogen. So the injection of nitrous oxide into an engine means that more oxygen is available during combustion. Because you have more oxygen, you can also inject more fuel, allowing the same engine to produce more power,and faster. Its not meant to "pump cold air".

500rpms is about where the happy time starts cruising (or when mine is set to) when u release the clutch after peddling. Nitrous will automatically rev your engine with out you opening the throttle.

So you're crusing and punch it as your going wot...you'll get up to speed fast (but its easy to over rev if u dont know when to stop spraying)

it will make up for the tq loss of the 27t sprocket which with the gear ratio, you'd get around 47mph MAX give or take.

im not sure what my 20" wheel will equate out to, i havent bothered with that yet.


also your wrong, there are ways of adjusting fuel
http://www.spookytoothcycles.com/component/virtuemart/?page=shop.product_details&flypage=vmj_ace.tpl&product_id=415&category_id=93

and then theres one non adjustable but it has larger ports
http://www.spookytoothcycles.com/in...id=93&vmcchk=1&option=com_virtuemart&Itemid=1
 
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I recognise those 2 carbs. the first is a Dakar. its a clone of a doletto, and uses the same jets. popular with the Moped crowd. the second is the revised version of what I have. Its on a 50cc peugeot right now, and works great. it marks its teritory well, too. the needle is ajustable, even if the jet isn't but jets can be redrilled. Both good carbs.

I'm only half serious about the NOS, though. looks amusing, and from the sound of it, it works, so probably worth the $40 just for the novelty.
 
An issue thats come up,
I have a Nexus 3 speed rear hub with the coaster brake.
the sprocket from my old kit's center hole is too small to fit around the outside of the hub. I could cut the hole bigger, but I'm lazy, and that would take some serious time with the tools I have avalable.

Are there any sprocket kits available for the multispeed hubs?
 
Drunkskunk,

I would look at using one of Creative Engineering's hubs. He could probably make the hole the size you'd need if you let him know.

As for the nitrous debate. I appreciate that everyone has determined to keep the conversation civil, I think it's good for the thread.

Now, you can re-jet for the nitrous (because you really don't want to run it lean on fuel with nitrous) but, when you stop spraying, how do you lean out the fuel since you don't need that much fuel when not on spray? My experience is that compensating for nitrous by increasing the fuel that much would make the engine's power output counter-productive once you "lifted" the NOS button. Would it be rich enough to 4-stroke at WOT, and what about lower throttle settings? I've always preferred supercharging over NOS because it's not an "all or nothing" power adder, even at part throttle, you still get some benefit of the supercharger. You set NOS up for one senario, WOT, and use it only when the button is set on KILL. At least, sucessfully.

Drunk,

That is a way cool bike. One that I DREAM of finding some day! Enjoy it!
 
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