Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

I got myself a nice almost showroom quality 79 Motron Medalist. I have never had such a complete and clean looking moped so understandably I don't really want to start tearing off shit and putting on fast performance parts (thats what my maxi is for) but I need a bit more speed to keep the drivers behind me sane.

At most I am willing to look into upgrading the pipe. And replacing or boreing out the carb (mines a 14:12 SHA).

What are some really simple things I can do to get a few more MPH out of her? I am not afraid to do some mild porting but I am not a port timing wiz kid like some of you guys so some pointers would be awesome.

I am currently topping out at 28-30 assuming that my speedo is accurate so not bad but people keep tailing my in a 25 zone so either people have lead feet or my speedo says I am going faster than I am. My attitude is that the drivers behind me can take another fucking road if they don't like following me.

Re: Stock mods to improve V1 top speeds

V1's seem pretty responsive to mild tuning. A high-flow air filter and a 60 jet had mine bouncing off of 36-38 with lots of low/mid power before I developed an air leak. Still idles like glass though and does a solid 35.

I'm planning on boring my carb, doing some mild porting, throwing a Cimatti 14mm intake on it, and adding a pipe like the Puch Techno Circuit, and then gearing up a touch.

With all the low/mid power, playing with gearing makes a lot of sense. As it is right now, off the line to about 30 mph I pull on some kitted bikes.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

How do remove the existing metal mesh filter in there? Does it just pop out?

Any hints on porting?

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

My 505a beats my V1 off the line. But ya its pretty good for a moped, no need to pedal from stop.

Re: Stock mods to improve V1 top speeds

Yeah, the metal filter pulls right out. I used a needle nose pliers. No matter what, you'll probably wind up bending up the edges a bit but shouldn't matter much. I forgot to add that I have a Treats HP coil on mine. Original wire & coil was pretty tired... the HP coil has spark to spare.

I'm not a porting expert by any means, so I'll recommend you ask someone who knows more than I do.

Re: Stock mods to improve V1 top speeds

for porting.... raise exhaust 1mm , widen exhaust 1.5mm both sides, match intake and exhaust ports to whatever manifold and pipe you're using. you can obviously go crazier but this will be a good starting point. the performance will be noticable. CHAMFER

if you're feeling it you can shave 1.00-1.50mm off the intake side piston skirt for a little more boosties. chamfer that too.

also I would recommend ditching the stock pipe... have you considered what kind of aftermarket one you were gonna possibly upgrade to?

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

I was thinking the mamba pipe. I need something with good lows and mids, I'm not building a high rpm screamer.

Thanks for the porting tips. Did you lose any lowend when you ported your stock cylinder?

Also I assume the V1s came in different versions, where are the identifying marks to know what version of the engine I have?

Re: Stock mods to improve V1 top speeds

The take-off might have been a little slower after the port job (being 110 pounds is hard to tell subtle low-end drops) but the map i gave you will complement a circuit pipe like the mamba nicely. With stock gears it should be a nice torque-y build topping out low 40s... get a 12t in front for 45 and a little less grunt down low.

I've personally never used a mamba (mounted a puch tecno circuit on my V1 cause mambas were outta stock) but I hear nothing but good reviews. So yeah grab a mamba... with the moderate porting you'll have a nice round-town bike.

In terms of the SHA... just make / buy a hi-flow air-filter for it, unless it needs replacing in which case you should get perhaps a 15.15 and a wider intake to match to your cylinder. ain't nothin wrong with the smaller dellortos though. except perhaps the lack of an adjustable needle.

Re: Stock mods to improve V1 top speeds

Darrell Gabbard /

just because you have a 14:12 doesnt mean that the intake manifold has a ID of 12mm it could measure 9mm and thats why you dont go over 30mph.

you should be able to get over 30 with a 10 tooth up front and a 42 sprocket on the rear wheel. and moped speedos are not really that accurate

Re: Stock mods to improve V1 top speeds

Puch intakes work well for SHA's on Motori minarelli, easy as fuck to bore on mill too.

i'm building a V1l Safari top tank late this season, Stockish w/pipe, writeups for sure.

Re: Stock mods to improve V1 top speeds

When I did a couple in the past. He hit 50mph on stock cylinder w/mamba, 19mm clone carbie, Ed's blue springs, 10-38 gearing. I chopped the piston on the intake side also .125 (edited)

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

great I just gave away a puch intake last night thinking I wouldn't need it.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

There a supposedly some good threads on V1 cylinder porting but I can't find any. :(

Re: Stock mods to improve V1 top speeds

🇮🇹💦 Of the Loin /

def hit over 50 with a polini 70/ blue springs/16sha mamba and 10/33 gearing

sure takes a little bit to get off the line tho

Re: Stock mods to improve V1 top speeds

🇮🇹💦 Of the Loin /

dont know why i even bothered to speak lol

id be interested in some stock porting if you find em, i havent had any luck either

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

Well cause we were talking about stock cylinders and you were talking about a Polini kit. Completely different leagues.

Tomorrow I am going to disassemble the top end make a pre and post porting maps and we'll see what what improvements it made.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

Re: Stock mods to improve V1 top speeds

i'll be doing this to mine pretty soon, should have numbers in a week or two.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

It's strange. The Motron runs very well, it just tops out at 25mph. I took apart the topend tonight out of curiosity. Both the intake and the manifold measure to 12mm, so I don't have the restrictive 25mph 9mm intake like some V1s but it acts like its restricted. Checked the pipe and its clear. Also the plug looks good. Such a clean machine, it was a pleasure to work on.

Re: Stock mods to improve V1 top speeds

Darrell Gabbard /

you then have a front sprocket of 9 teeth and a rear of 44-46 or more

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

Well, I did what Morgan said to do.

I widened and raised the exhaust port 1mm each side,

took 1mm of the piston skirt intake side,

Also I made my SHA 14:12 a 14:14 and widened the intake manifold to 14mm and matched the intake window to 14mm.

In the process of drilling out my intake manifold I went through one of the walls. I JB welded it by rolling up some gasket material and sticking it in the intake to keep the JB from running into the manifold and applying the JB on the outside. It seems ok to me, at least for now. So I had to let the intake sit off the moped overnight and was unable to test my improvements yet.

Will report back with my findings.

Re: Stock mods to improve V1 top speeds

funke,

You'll need some blue clutch springs. Them old ones won't let you wing it out. If you port the base of the cylinder, that's where you get alot of power also.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

I'm having an odd issue where it will run but not idle for anything. I feel like keanu reeves in the movie speed where I can't go under 20 without dying. After all that I noticed no speed increase either. Thinking the issues might be related.

I need more jets too all I have is the stock #52 and a #63.

Re: Stock mods to improve V1 top speeds

🇮🇹💦 Of the Loin /

your idle passage is clogged

I usually take an old brake cable, unspool ONE of the little braided wires, and run it through that tiny hole below the base of your venturi (look on the air filter side)

also, if you bored out your carb, and had to remove and reposition the emulsion tube, make sure the bottom hole in the tube lines up with that tiny hole i told you to clean, because if they don't, you won't idle.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

Thanks. I didn't remove the emulsion tube because the cab opens up to 14mm before it. Just dremmeled it, which is probably why it's clogged.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

Well I made sure the idle passage was clear. Still won't idle.

Re: Stock mods to improve V1 top speeds

oh no!

find another carbie and retry, worth a shot? Moore jetting? well a range of jets? (edited)

Re: Stock mods to improve V1 top speeds

yikes do you have another carb you can test out?

also how's your fuel flow? have you cleaned out your banjo in the SHA recently?

edit; also what air filter are you using right now? (edited)

Re: Stock mods to improve V1 top speeds

kim jensen /

Hey Luke, yeah when you open the carb up you may need to enlarge the idle hole in the little copper tube in the SHA. Take a leedle large enough to fit into the hole (holes) in it and gently widen the opening slightly. Also make sure your idle screw is turned in - probably all the way.

I haven't been able to test mine much because I need an 11mm cone lock nut on the rear wheel before I can drive it.

I did the piston and cylinder porting mentioned above and on my one test it seemed quite a bit faster than the 25 stock. I only put a 54 jet in it, may need to go bigger. Mine had the super restricted 14-9 with the narrow intake- also now bored to 12mm.

You should be on the right track.

Re: Stock mods to improve V1 top speeds

Luke “Funkenet” Hosfield /

Fuel flow is fine. Stock filter. I'm gonna try widening the hole. Which do I widen the smaller of the two I assume.

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