Honda Express

Can anybody tell me if they have used a 70cc kit for a Honda Express. If so did you have to change the Jet? Anything else besides the obvious. This is my first one and I am not sure what to expect?

Re: Honda Express

most hobbit ones are easily adaptable, better get whole new carb, not just jet. try searching "express mods" for more ideas/answers.

Re: Honda Express

I don't have an extra kit, don't think that you'll find anyone that is willing to part with theirs. Here's a pic of mine. You'll really need another carb & pipe to get the full benefit of the larger displacement. The kit will give you more torque but it needs more air flow in and out to do so.

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Re: Honda Express

Thank you very much. Will the original carb work, or is it a waste of time. What kind of increase can I expect?

Re: Honda Express

Thank you very much. Do you have a recommendation on what carb to buy and where? Will the original work for the time, or not at all?

Re: Honda Express

the original carb is pretty small, if you're going to spend the time putting a kit on you might as well go for a larger carb. I am not a fan of the hobbit carb. it's a butterfly carb, not a slide carb like the stock express. either a SHA or PHBG would probably be better for you. You're gonna have to get creative with the intake though... Check this thread break>

You should probably get a pipe too, the stock one isn't the greatest. Treats has either the Jamarcol (cheaper) or the Proma (expensive / out of stock) listed on his site.

You could run stock pipe & carb with an upjet, I know Graham from Milwaukee put a 70cc DR kit on an express for another one of the Milwaukee guys, and it's definitely a ripper, but probably has vastly more potential with a carb & pipe.

Re: Honda Express

The original carb & pipe are a waste of time. I'd buy a good pipe and a carb before the kit, probably a 19 PBGH or a 20mm Mikki if you plan on kitting up w/ a stock 2-petal reed.

Steveo - Nice carb & manifold setup, but have you ever considered buying a couple of cans of electrical contact cleaner or some Gunk? ; )

Re: Honda Express

I have been tuning on expresses pretty hard this year. My personal experience is you are going to be best off with a carb in the 16-19mm area, and probably either the treats jamarcol pipe, or fabricate something out of a pocket bike pipe. They are super cheap on e-bay and if you cut up your stock pipe, take the header and weld it to the expansion chamber of the pocket bike pipe, it'll get you another 5+ mph. Both Rick, myself, and a guy that posts as expressmentor have done some pretty good right ups on express tuning. search around the performance tuning forum for stuff like nc50 mod, express speed, that kind of thing.

But yeah, stock carb is not gonna work for a kit. I can point you in the direction I took if you want to know.

Re: Honda Express

Sorry for my ignorance but is the 16 to 19mm the jet or a whole new carb. If it is a carb can you recomend an inexpensive one? If I use the Jamarcol pipe will it need any modifications, or will it bolt rite on? thanks again for you help.

Re: Honda Express

What pipe have you used? Will the carb kit alone make a difference, or do you need to use everything together. Are the 19 PBGH or a 20mm Mikki carbs? What is kiting up with the reed. I didnt know the reeds were an issue? Can I leave the current ones alone? Sorry for the ignorance, I am new at this. I really appreciate your help.

What would I use the gunk or contact cleaner for?

Re: Honda Express

Thanks for the awesome pic. I did already buy the DR kit and havnt opened it yet. Not knowing very much about this I didnt even think of the pipe or carb being necessary. If I am understanding correctly, the stock carb and pipe will work but I need to change the Jet? This would be a great money saver if possible. Do you have a recomendation on a jet size? Have you used the Jamarcol pipe? Is it crazy loud? Does it bolt rite on?

Re: Honda Express

Reeds are another good suggestion! I put a set of the 2-stage Boyesen's on a friend's express not that long ago, WICKED!!! Way better than those flimsy metal pieces of junk that are stock. the reeds are on a "reed block" between your intake and case. They're not the easiest thing to get to, but if you disconnect the rear shock you should be able to get to them without much of a problem. Took me about an hour to do. breaking the screws free without stripping / breaking heads off of them was the worst part. had to drill and easy-out one that the screw head stripped on.

19mm refers to the carb's size, not the jet. don't totally cheap out on a carb, you get what you pay for. expect to pay at least like $60 for a new carb. if you want you could try the OKO (which is more or less a Mikuni) but I think the smallest size treats has is 21mm. I have one and WOW, it's big, a real MONSTER!! Otherwise, if you're brave, you could try the 15mm Bing, you lose your thumb cable choke thingy though. If you're a newbie, a SHA or Bing would probably be your best bet, the PHBG & OKO have lots of tuning possibilities but may be hard to dial in. your intake manifold will probably limit your carb's size / efficiency though.

Check the Wiki and tuning spreadsheet, they've got lots of useful information about carbs, pipes, reeds, repairs, tuning, and what other people's results have been.

@Rick, that's actually not mine. I just found it as a reference. I agree, that's pretty nasty looking, my swinger is nice & shiny!

Re: Honda Express

here is a pic of what i did. the bike was found in the trash. i have been workin on hobbits so i simplified this project by using parts i had laying around. it runs and is on the bike now

1244489468_wtf_001.jpg

Re: Honda Express

it got painted yesteray

1244489645_hobbit_express_002.jpg

Re: Honda Express

/\ that should be new bike of the week pic

Re: Honda Express

stever: stop posting /

whoa, that looks pretty fucking sweet. when you paint the bike, paint the sidecover to match.

Re: Honda Express

Jbren, the 16-19mm is in reference to a new carb. I can point you in the direction of a cheap 19mm carb that will work for you. Also yes, the jamaracol pipe will bolt on and will give you speed. But you will have to make some support for it in the back.

Thats a pic of the little bracket deal I fabbed up. Its not perfect, but it works. I think if I remember right its made out of a metal shelf I found on the curb and a butter knife.

This is the carb I use now.

http://shop.hkmotos.com/product_info.php/products_id/69?osCsid=19adf54b06ce68b9a92f6e2b8edb90cc

I used the little rubber and metal intake thing it comes with to attach it to my express intake. It actually works really well.

Honestly though dude, I would just play around with a pipe, a nice uni pod air filter, maybe some nice reeds, and the stock carb for a little while. I wouldn't kit it right away, chances are you are going to be disappointed or wreck your kit and maybe your engine. Get the most speed you can out of the stock cylinder, then kit it.

Once you can go over thirty five on the flats on the stock cylinder for a long ride, then you are ready to kit.

Re: Honda Express

thanx doods the hobbit expess is a side project i'm makin for my dad. i got him interested in mopeds by making him go on rides with me. he's cool. i had the hobbit frame layin around and got an idea. the hobbit tank came in handy also. it was more manageable to clean. here's a pic of my bike in the process

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Re: Honda Express

Stevemke, Thank you again. Like an idiot I ordered the kit before taking the time to learn. It never occurred to me that there would be so many variables. You had mentioned in your previous posting that I may be able to upjet. Would there be any improvement by doing this with the DR kit? If not I wont, but I am only looking for 4-6 mph. The bike looks original, has only 400 miles on it, and I was hoping to keep the clean look. At the same time I dont want to damage it. Please advise.

Re: Honda Express

Okay, I think there's some confusion going on here. The carburetor determines how much fuel and air passes into your engine. A moped needs a specific ratio of fuel to air -- to much fuel in the ratio is "rich" and too much air in the ratio is "lean." Both of these conditions will hurt the performance of your moped, and running lean can damage or destroy your engine. When you put a kit on, more air will be going through your engine. To compensate for that extra air, you need more fuel. The jet is the part in the carburetor that controls the fuel flow. Different sized jets have different sized holes -- the bigger the number/size, the bigger the hole, and the more fuel that will flow into the engine. This is why, at the very least, you need to install a new jet in your carburetor when you put on a kit -- otherwise you will be running lean, and you will probably damage your engine.

When installing a kit, it is better to install a larger carburetor (not just jet) to get the most out of the kit. The kit will draw more air through the engine, but it won't be able to pull all the air it could potentially be using through a small stock carb (think of trying to breath through a really small straw). If you get the bigger carb, you give the engine more air. This larger carb will have the correct jet in it to maintain the right fuel to air ratio, but you will be getting more of that ratio through the engine, which will give you more power.

Re: Honda Express

Thank you so much! how fast have you been able to get your bike moving. Stevemke was nice enough to give me some great advice as using the larger carb or at least a larger jet. I was telling stevemke that I foolishly already bought the 70cc kit. If I try this without the carb can you suggest a jet size to use?

Re: Honda Express

Got it, thank you!! If I use the cheep way for the moment can you suggest a propper jet size to use?

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