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Discussion Starter #1
This project has taken a long time. Mostly because I'm a finicky old fool and if it don't come out right I keep doing it! I did have it up to pedal status for a check on the hydraulic discs and here's an ugly before paint pic;



After paint and now it's looking like a Ferrari ..


Next up is re-fitting the pipe and since I'll be cuttin' on it anyway I'm wondering about modifications. I've read about adding 4" to the belly area, plan A is to do that, but I'm looking for a wide power band torque motor and not sure if that's a good idea or not. Opinions are welcome ...


I've also been following SilverBullitt's thread very closely cuz motor work is next and I'm hoping to save CAM some typing. :)
 

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This project has taken a long time. Mostly because I'm a finicky old fool and if it don't come out right I keep doing it! I did have it up to pedal status for a check on the hydraulic discs and here's an ugly before paint pic;



Next up is re-fitting the pipe and since I'll be cuttin' on it anyway I'm wondering about modifications. I've read about adding 4" to the belly area, plan A is to do that, but I'm looking for a wide power band torque motor and not sure if that's a good idea or not. Opinions are welcome ...


I've also been following SilverBullitt's thread very closely cuz motor work is next and I'm hoping to save CAM some typing.
Looks Awesome...…….Cant wait to see the finished product...!

And a Huge Thank You from My Fingers too...LOL

You know that if at any time you need any advice or help its no bother aslong as its utilized….LOL

The reality of the situation as you already know where the engines originate from and if you used a degree wheel to get the dimensions and the degrees of that bone stock engine then run the numbers through a pipe program you'd see that the pipe the Chinese utilize isn't even close to whats recommended...

Sure for a bone stock engine in the first stages of mods and wanting cheap extra power adding 4" to the belly worked out descently…

On tool engines Im a firm proponent of getting the exhaust out of the engine as quickly or as easy as possible...

If you take the total area of the exhaust port at the flange that should be the starting size of the inner diameter of the J-bend pipe after a nice sweeping J-bend with a pipe of correct diameter inside it must converge larger as it enters the expansion chamber so that place of convergence helps with resonance waves and their effects on powerbands......The Chinese just stick the pipe in and weld it....How is it supposed to converge correctly?..

Heres some crappy vids Im sure you may of seen...

In the first heat cycling vid you can hear the fully blueprinted and mildly modded 40mm bore 1pc stock cylinder with ground-in third port and othr extensive mods youre reading about on Silverbullets page to make it the snippy lil powerhouse looking to bust out...

On these small 2 strokers the more they are corked up the quicker they'll rev at idle...

The stock expansion chamber was cut off due to having a heavily imposed EPA device that kills power and I welded a rev pipe from an X1 that I modified and put in its place....

trophy cag modded exhaust 1 by Dizzy Gillespie, on Flickr

On the first run after heat cycling the thing ran strong but slowly lost its chug from being restricted due to the size of the whimpy stock J-bend which was like 19mm's inner diameter so I removed the stinger and as in this next vid made the engine breathe a lil easier and the revs time out a lot differently too but it was still being held back...….....LOL

trophy cag modded exhaust 2 by Dizzy Gillespie, on Flickr

Then I designed my dual chamber rev pipe that I stole the idea from my 137cc Methanol powered racekart that does 133mph...Notice where the exhaust exits from on this pipe......Internally the exhaust takes a longer path than whats seen by the eye...…...Same as my pipe.....LOL.



Not only does the exhaust rev a lot free-er with zero restriction its also a lot quieter compared to the stock modded pipe...….

trophy cag modded exhaust 3rp by Dizzy Gillespie, on Flickr
 

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Don't sell yourself short, you did a great job. I wonder if the SS Pro Jet S exhaust would mount to the engine and bike frame?
 

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Don't sell yourself short, you did a great job. I wonder if the SS Pro Jet S exhaust would mount to the engine and bike frame?
If he plans on doing the mods he needs for the all around powerband those ProJets don't work as intended on any engine that has more than mild mods...

Everybody claims theyre the best and what not...If this was evident wouldn't a company like ProJet want more customers and one way to get those customers is with videos showing how much performance you can get and hear the exhaust tone etc...Dyno sheets with engine specs help alot too proving it's efficiency...

This is a vid of my 16.5:1 methanol/alky engine I built with 6.0volt auto advancing CDI....The video makes me look like Im totally manhandling the pullstring but alls Ill say is until you yanked that much compression without a glove only those will know the strain on the joints....LOL…..LOL

Listen to how the Jet Pro holds back the revs...Its not like it was running top notch but it should of revved a lot cleaner and exhaust tone shouldof been more enhanced and timed a lot slower......If I can find the vid where I put the dual chamber rev pipe on it the difference is like night and day...Kind of like the trophy cags progression....LOL

black magic cag by Dizzy Gillespie, on Flickr

Even this pipe outperformed the JetPro on the BMC...Its one I made for the Evil Wasp cag



That pipe above is on the bike in the video below..Even though the exhaust looked and also sounded like it was free flowing it was still held back a lil to where I went and built what I called Dr Overkill but actually wasn't...………...LOL

033 by Dizzy Gillespie, on Flickr
 

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One thing I tell everybody that wants to make a motorized bicycle or even a stand-up scooter where its gonna be held at speeds for extended periods of time is that reeded engines don't make good engines for such tasks unless youre running them in the 4500-5000rpm range and building them for brutal torque,,

The better engines are the piston ported engines....

I know the logic seems sound and almost everybody chooses the engine and its the pricetag of one that's the swaying factor......LOL

The reeded engine comes 40mm x 32mm and 44mm x 32mm...The piston ported engines come 40mm x 34mm and 44mm x 34mm....

Heres a small engine calculator and you can see where the two engines with 44mm bore stand in each of its relative stroke...

http://performancetrends.com/Calculators/Engine-Displacement/Engine-Displacement.php

Piston ported engines are always timed the same and can be more repetitive in the performance area because reeds don't open and close at the same rate and don't always seal perfectly etc...A piston that controls that action has way better control therefore can deliver the better overall useability you desire...

Its not hard to change from what you have by simply buying a piston ported engine plate and bolting it atop the cag mount when your ready but use it as very good food for thought the first time that engine gets a reed failure and your pedaling home wondering what happened.....

If I was gonna pick an engine for the mode of transport you chose and want the overall useability with good lowend all the way to topend revs that would be the Piston Ported engine hands down...……Its 51.698cc's with more torque than a 49cc reed inducted engine with room for easy expansion with a dremel....

Like I said keep it in the back of your mind....

This ones just mildly ported but the torque factor is insane......LOL

I can rip circle wheelies all day on it....Try that on a scooter with GP460 high revving piston ported engine or even a modified cag engine....You have to get up over 10-15mph to rip wheelies on those....LOL




To put the point more direct and to the point...Im not saying all reeded engines are racing types but if you wanted a nice cruiser car or pickup with nice smooth power youre not gonna drop a Chevy 572 crate engine in it that's for sure and if you've ever driven a hotrod with a considerable sized camshaft through town in rush hour traffic you know how hard it is not to cause a ruckus every time you have to restart or make any mamby pamby with a kid nervous causing them to hold their kids hand more tightly and keep them tightly by their side plus Im sure you've experienced or heard of the stories of some carrying around sandpaper or extra sparkplugs in the toolbox or glovebox for when the plugs fouled out.....LOL

Kind of the same analogy between reeded engines and piston ported engines...Reeded engines need to be flogged more often than piston ported engines as the jug tends to build-up faster when you use a restrictive pipe and a J-bend that easily collects the unburnt oil and fuel when being driven at low speeds to cause that fouling...

Id use a modified box muffler bolted to the end of a 5" long 1 1/8" ID headpipe with a flange welded at each end...That should keep the engine from being fouled by unburnt oils getting trapped in the J-bend when just cruising along or a descent underbelly pipe..

If you look at the scooter in the picture youll notice the powerplant affixed atop the frame....That engine didn't last very long and was the first and last time I put a reeded engine on anything I ride long distances.......…...LOL
 

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Discussion Starter #6
I'll go with the 4" belly for now but who knows what the future will bring. Building a properly tuned expansion chamber is on my bucket list tho. It could happen.

As far as motor selection I started with this reed valve before I even knew the piston port existed, but I've got 2 of them now. That could happen too. A P/P with a properly designed downpipe? That'd be cool ..... :)
 

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Adding 4" to the center of the belly will make a difference. I got a short section of 1 ton diesel Ford truck pipe section, $20 I can cut into 4 pieces or 4 pipes. The chrome pipe is an under the engine and up then out the back. I modified one into a side pipe for my Lucky 7 Reed Port Cag. If you look the foot pegs are on the front axle helps keep the front wheel down, lol. It also has water cooled C1 forks and dual front disc.
 

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I don't know where it came from but I got 2ft of rusty 2 3/8" thinwall tubing that'll work just fine. I never throw anything away .... It's a disease.
 

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That's funny cause my wife calls me a Horder, lol, lol. She says I should open a pocket bike parts store.
 

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I'll go with the 4" belly for now but who knows what the future will bring. Building a properly tuned expansion chamber is on my bucket list tho. It could happen.

As far as motor selection I started with this reed valve before I even knew the piston port existed, but I've got 2 of them now. That could happen too. A P/P with a properly designed downpipe? That'd be cool .....
Absolutely and I figured so as far as this all started..Like I said the other DIY bike guys started with them because they were $80 bux compared to $130.00 plus the style of the reeded engines fits into bicycle frames a lot easier but for reference nobody says a piston ported engine with pumper carb has to be mounted with cylinder in the upward position.... LOL

Like I said Im just throwing it out there as food for thought...

Then for the hardcore entusiests it all progresses to this point in the quest for torque and overall reliability which is short of stuffing a 6.5 predator in there...LOL...………………



One day I'll finish this one..I think you've seen it.…..It has a OHV 8hp engine made by the Chrysler Outboard Corporation then by Teledyne WFI for the US Military and was first built in 1952 with no changes all the way up to 1987.....

Im looking to mount a Torque-A-Verter transmission to it...I already have the governor modified for the engine to deliver 4500rpm's easily

Its the very first OHV industrial engine that was way way before briggs,honda and techumseh's time that's for sure....LOL.Its got mondo torque and is more like a car engine than most realize.It has an automotive crank driven oil pump too with automotive style oilpan....It also has a CDI ignition system with whats called a "Lifetime Sparkplug".......LOL





Other powerplants of mine include diesel power aswell...One day Ill put these engines below on some sweet projects....
 

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Discussion Starter #11
Yup.The bug done bit me.

I've already got a 6.5 horse OHV Briggs with an electric starter on the shelf that'll probably be the next project. Plan A is to start with the headstock and front downtubes off an old Yamaha and build my own frame from there. It'll need a battery and some way to charge it. A headlight, brake/tail light, and horn are in the "might as well' category. Some form of rudimentary suspension is gonna be a requirement. A pothole at 35-40 mph? I'm thinking an old skool springer front end and a sprung hub in the back like the old Norton Featherbed. I could make that ... For that Board Track Look I'll use 21" motorcycle rims on both ends with D.O.T. rubber. Make my on hubs again? Who knows? :)

Another possibility is using the pair of 5 horse Briggs flatheads I've been saving on the back of a 3 wheeler. I'll bet that'd do wheelies! I've also got this cute little Staton differential with 1" axles that needs something to do.

But I better finish this Schwinn first.
 

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Yup.The bug done bit me.

I've already got a 6.5 horse OHV Briggs with an electric starter on the shelf that'll probably be the next project. Plan A is to start with the headstock and front downtubes off an old Yamaha and build my own frame from there. It'll need a battery and some way to charge it. A headlight, brake/tail light, and horn are in the "might as well' category. Some form of rudimentary suspension is gonna be a requirement. A pothole at 35-40 mph? I'm thinking an old skool springer front end and a sprung hub in the back like the old Norton Featherbed. I could make that ... For that Board Track Look I'll use 21" motorcycle rims on both ends with D.O.T. rubber. Make my on hubs again? Who knows? :)

Another possibility is using the pair of 5 horse Briggs flatheads I've been saving on the back of a 3 wheeler. I'll bet that'd do wheelies! I've also got this cute little Staton differential with 1" axles that needs something to do.

But I better finish this Schwinn first.
That's funny...……………..Sometimes I'm convinced Ive become the bug...…..LOL
 

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Discussion Starter #13
Got my pipe re-fitted and a 4" belly welded in;





And I'm gettin' ready for the motor;






I've never bought a burr in my life, just sort of "collected" them along the way. And I ain't impressed with the current inventory! They might cut aluminum .... :) I dunno.


The sanding and polishing inventory is fine, but I'd like to buy some useful carbide burrs for what I'm about to attempt. Recommendations?
 

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Got my pipe re-fitted and a 4" belly welded in;





And I'm gettin' ready for the motor;





I've never bought a burr in my life, just sort of "collected" them along the way. And I ain't impressed with the current inventory! They might cut aluminum .... I dunno.


The sanding and polishing inventory is fine, but I'd like to buy some useful carbide burrs for what I'm about to attempt. Recommendations?
Looks like you're on your way......From what I see the current inventory should cut the mustard as its easier to control tools that aren't as sharp so you don't accidently remove too much material...…

I usually prep the cutters and raspers by dipping them in acid sort of how you sharpen files....You can use a diamond sharpening card with mineral oil too....

Alls you need is some jewelers files and some emery paper in both 100 grit and 2000 grit...…..

You can see the crap I use.....Even drill mounted wood raspers work good at doing the initial cuts...…..

That stock pipe mod looks good...……...




 

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Killer job on the pipe, I mod all of my reed plates and stops, I like carbon fiber reeds, I cut ,200" off the top of the alum reed stop tips, then grind the inside back on an arc so the reeds can open more, if you go too far back the reeds will hit the crank. I had some riding on my full circle crank.
 

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I decided to give those cutters a shot and they did just fine. Mighta cut too much off by that screwhole but it's smoothed out





Next up I need to do the other side, but I'm already wondering how I'm gonna get the cases blended to the transfer ports. They're a mess.




You can see how one's deeper than the other and they sure don't match the case. Not liking the cylinder skirt either ....
 

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Typical problem, I use an 8" 3/4hp bench grinder and a $10 Home Depot 4" angle grinder for the heavy stuff and a couple of china dremels and high speed cutters, and of course files an sandpaper 100 to 1,000 grit. The case mods look good.
 

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I decided to give those cutters a shot and they did just fine. Mighta cut too much off by that screwhole but it's smoothed out




Next up I need to do the other side, but I'm already wondering how I'm gonna get the cases blended to the transfer ports. They're a mess.



You can see how one's deeper than the other and they sure don't match the case. Not liking the cylinder skirt either ....
Beautiful job for a start....If you want perfection waste $$ on a milling machine or lathe I always say....LOL

First chop the flowside skirts on an angle to get rid of the triangle of turbulence then open up and re-shape your transferports ..After that bolt a crankcase half on it and mark with a sharpie all the places you need to enhance the flowpath while trying to remove as little of aluminum possible.....……..That's where the emory paper and grinding stones on drill arbors comes into play...

I do a process of grind then sandpaper finish regrind then refinish until I get that perfect shape for the build.

Thats how it gets such a smooth flowing look to it..

Keeping track of the aluminum waste is a plus as-is doing the mirror image soon after doing the master copy while its fresh in your mind...…Im ambidextrous so doing the left-hand case is just as easy doing the right for me but its not the case for everybody...

Aslong as you don't surpass that tipping point the advantages to blueprinting over not doing it are huge...………….

I do my cutting over parchment or wax paper over a large workboot box and try to recover as much aluminum chips as I can to collect weigh and compare....




 

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Next cases you do don't grind away the aluminum so much near the bolt hole although it may work in your favor when grinding-in a 3rd or 4th port....

You want to define a flowpath that kicks the mix towards the transferports also boostports...….

You can get the idea better from looking at a blueprinted piston ported casehalf….



The cylinder skirt area on your cylinder is indeed a slight mess as that's the nature of the Chinese and the cheapness of the tool based engine but from what I see will sculpt quite nicely..Once you get the eye youre golden....

As you can see I even handport aluminum cylinder heads that are designed to already enhance performance...…...LOL

 
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