General Homie Forum
 

I am starting a Homie conversion and I thought it would helpful, not only for myself but others, to have a sub-category from the main conversion heading, making specific engine information easier to find.

Maybe I just think too much.

Anyway Hears my question: I started tearing down my Homie 30 and the stock intake runner is only 12.5mm, and the cyl. is the same. The WT-258 11.11mm carb I intended to use is 15mm at the manifold.

Do I have to re-work the intake port on the cyl. or get a different carb?
I do intend on getting a "twister" manifold and I assume the runner will be larger than the stock manifold runner.

RE: General Homie Forum
 

If you are going to change insulators eventually, just leave your old one alone. It will run pretty good without inlarging it. But would run better if enlarged.

Some of the 11.11 mm carbs have smaller diameter butterfly diameters but they are all bigger than the stock insulator dimension.

RE: General Homie Forum
 

So, what your saying is I don't necessarily have to modify the "insulator" for now.

Even if I change the insulator or enlarge the existing one, the port on the cyl. is still going to be the size of the stock insulator, then what?

RE: General Homie Forum
 

I emailed wackerengines re: their twisted manifold for the Homie but I got an email back that seemed to have some attitude. They suggested that I purchase from another supplier. All I asked for was, some more detailed info and pics of the part. I just wanted this info to get an idea of how it would fit, not steal their secrets, as maybe they felt.

If it looked like it would work I would have purchased it. Now, maybe I will take their advice.

RE: General Homie Forum
 

Here is a picture of a Homelite "twister" manifold, modified for a larger carb. You fill in the areas around the throat with JB Weld or similar, then enlarge to match the carb throat. You also enlarge/bevel/smooth the intake port to match, but do not remove the little "nub" in the top of the port as this is to keep the ring from catching in the port at BDC. Once you modify the manifold like this, you have to set the carb up for external pulse to operate the fuel pump. Note that I do not recommend trying to drill out the manifold, as the large drill bit can easily "catch" in the relatively soft material of the manifold, and break it or tear it up. I use a drum sander in my Dremel to enlarge them. It goes fast...

Here are a couple of links that might interest you with lots of Homelite info:

http://www.rcuniverse.com/forum/m_26...tm.htm#2621860

http://www.rcuniverse.com/forum/m_23..._1/key_/tm.htm (Refer to post # 39 in this thread)

The third pic is of a Homelite with the external pulse setup on the carb, but that particular installation does not have the "twister" manifold. It has the normal one, but also modified as shown. Man, it took me an hour searching through all the pics on my computer for these pics....

Have fun,
AV8TOR

RE: General Homie Forum
 

Thanks AVATOR.
I was afraid you would say grinding would be necessary, good parts get ruined that way.

RE: General Homie Forum
 

Go slow, check often...

AV8TOR

RE: General Homie Forum
 

I thought this would be a good spot for a homelite question....

How do you remove the steel lugs in the flywheel that hold the pull starter paws?

RE: General Homie Forum
 

Drive them out from the back side with a pin punch. Sometimes there is a small amount of flash over the holes where the pins are, but it will break through easily. Careful to support the flywheel so that it is not damaged.

RE: General Homie Forum
 

yeah, I have a 4x4 that I drilled a 1/2" hole in, place the flywheel pin over the hole and drive it through.

RE: General Homie Forum
 

"How do you remove the steel lugs in the flywheel that hold the pull starter paws? "

They cease to be a problem when I throw the flywheel away.

:)

RE: General Homie Forum
 

Please give them to those that use them in which to mount their electonic CDI magnet. Just use a hole cutter to remove the center of the flywheel, clean it up bit, the drill the hole for the magnet.

RE: General Homie Forum
 

I've done it many times that way as well...

AV8TOR

RE: General Homie Forum
 

I have a solid oak 2x4 block with depressions drilled large enough for the "starter paws" to go down into as I'm driving them out. You have the whack the splined pins pretty hard. I've broken several punches getting them out.

RE: General Homie Forum
 

Av8tor, I saw in one of your older posts a Homie muffler that you had split so it could be gutted.

Can you tell me how you got it apart and how did you re-join it together. I intend to buy an after market muffler later but I would like to gut the stock muffler to save some money while I'm still testing. I only have the one muffler, so I only get one shot at it.

RE: General Homie Forum
 

It is a little bit of a pain in the butt, however it can be done. I just take a screw driver and work my way around the crimp, undoing/opening the crimp. Be careful, it is easy to slip and stab yourself somewhere with the screwdriver. Work it a little at a time so as to not damage/tear up the crimp, until you get the crimp open and can take the muffler apart. Then you can gut the muffler. Take everything out except the bolt supports that keep the muffler from crushing when the bolts are tightened down. Then you can add your outlet tubes. Ideally silver braze works great to braze light weight thin wall brass tubes in place, but the silver braze is very expensive. You can use regular common braze to braze the tubes in, but in that case it would probably be better to use steel tubes and the brass tubes are so thinwall that they are a bit tough to braze without burning through them. Then you can recrimp the muffler back together using pliers to start the crimp closing, and a hammer against a hard surface to finish closing and securing the crimp once again. It is optional to use some JB Weld as a sealer so that the crimped seam will for sure not leak...

The mufflers I have done this way hold up indefinitely, make good power if you install large outlet tubes, and are considerably lighter than the aluminum aftermarket mufflers. Sometimes the mufflers have a large hunk of steel inside instead of tubes to prevent the muffler from collapsing. In those cases to save weight I make up some tubes for bolt support, and throw the heavy chunk of steel away. Automotive steel brake line tubing (large size) or fuel tubing (small size) makes good bolt spacer material.

AV8TOR

P.S. Here are some pictures of one I did differently because it was long and I needed to shorten it. I sawed the muffler in two, then made a metal cap that I gas welded on. Added the two tubes, cleaned and painted, and there you have it. I actually made two of these for my custom twin.

RE: General Homie Forum
 

I converted the stock muffler today. It was a pain. I ground off the crimp instead of bending it open and brazed halves back together and installed a 1/2 inch EMT conduit for an outlet. It's rough looking but functional. The engine is stock except for the now modified muffler. I got 6800 RPMs. with a 17/8 Xoar prop. Thats an increase of 500 RPMs over the 6300 box stock configuration. I was hoping for more after seeing how much baffling was in the muffler. I'm still a long way from the 7500 to 8000 some are getting. I'm planning to remove the 9.53mm carb and test with a 11mm carb on stock intake to see what will do. I'm not expecting much though maybe 200 RPMs
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RE: General Homie Forum
 

I think the hot muffler setup is twin 3/4 inch outlet pipes. Maybe your exhaust is still too restricted. Maybe do a search on Homie mods, I am sure the muffler mod was somewhere on RCU.

RE: General Homie Forum
 

Your muffler looks fine. It just needs a good wire brushing and painting.

I like two outlet tubes of at least 1/2" i.d. for 25cc engines. Bigger is better...

I think you will notice a nice difference with a larger carb. However, when looking for power, I always recommend that people check the ring gap. It is almost always too large. Optimal stock ring gap is .003". That's about the width of a piece of paper.... Any larger is giving away power, and most used engines I take apart have an excessive gap. Try Frank Bowman for rings.

I once did an experiment. I had a Homelite 30cc with a larger than optimum ring gap, (about .020"). I ran the engine and it started, idled, and ran well. Then I put a Frank Bowman ring in it, and after only one tankful the rpms were up by 800!!

AV8TOR

RE: General Homie Forum
 

I plan on getting a set of rings from Frank. The engine does have a bit of leak down when you turn it over slowly. If I can get only 500 more RPMs with new rings, I'll be very satisfied. I made a velocity stack out of a 3/4" PVC plumbing fitting today for testing purposes. I got another 100 RPM and had to lean the high needle 1/2 a turn.

Do you thing the stock fins on the flywheel are draging the RPMs down.

RE: General Homie Forum
 

Neat idea on the velocity stack. I tend to get tunnel vision and over look materials, like plastic. PVC when properly glued fuses the material into one piece. A piece of PVC pipe glued to a pvc washer would probably work out great.

I have bene making mine form copper water pipe and aluminum tube from tent poles and lawn furniture. First I anneal the tubing with a propane torch. I then chuck it in my lathe. I then set up a fulcrum with the tool post. Grease up the inside of the tube and "spin" it. I use the lathe jaw chuck key as my spinning tool. It has a handle made out of 3/8" material with a nice smooth radius on the end. Spinning is really easy. It is no trouble to work the material out to 90-degrees and up against the chuck jaws. You end up with a top hat shape.

RE: General Homie Forum
 

I'm not sure I "follow" that.... Got any pics??

AV8TOR

RE: General Homie Forum
 

Sorry, not right now. If folks are interested I guess I could take some pictures.

Let me try again. Take a piece of aluminum tubing the size of the velocity stack body you want, say 6". Put a little soot on one end by choking off the air on the torch. Heat the tubing, holding it with something other than your bare hand, by playing you torch flame on the metal end you intend to spin. Twirl it around to do it evenly. Plunge in water. The material will now be very soft. Chuck it in the 3-jaw with about an inch sticking out. Face it off and touch it up with some sandpaper to round the edges, please don't cookie cutter a piece out of your hand! Set up a tool holder, I use my boring bar holder, to give you good leverage to pull athe the tubing from the inside. Use a long polished round rod with a rounded end to do the pulling by leverage. Put some grease inside the tubing so it does not gall. turn the work as fast as you lathe goes. You will find as you push the inside of the tubing out it stays that way. Work the tubing to larger and larger diameters untim it is time to bring it back against the chuck to make your flange.

It is like throwing a clay pot on a potter's wheel. I found some articals on the net on "metal spinning". Check it out. It is fun. At one time I had plans to spin a metal cowl. For that kind of thing you need to make forms to spin against. Your local aircraft shop should have buckets of fancy aluminum sheet the recycle bin. Some of it is hard some very soft. You want soft. It will work harden.

RE: General Homie Forum
 

Hmmm, that's interesting. Yeah, if you could post some pics too that would be great.

Thanks,
AV8TOR

RE: General Homie Forum
 

My problem is I don't have a lathe so I'm at a bit of a disadvantage. I have to do everything with hand tools. I don't know what I would do, without the dremel I bought at a garage sale. The "intake stack" was made out of a 1 1/4 x 3/4 PVC pipe reducer. I cut off the slip female end flush with my band saw. I wish I had a lathe so I could turn off the male threads to make it look better. I will most likely buy an aluminum one for the final cut.