Stock a35 modding.

Who has ported and modded stock a35s? I’be searched and searched and read and read, but I still need some insight.

My idea:

1mm base spacer w/gaskets top and bottom. (To raise transfer and boost ports because I lack tooling to modify them.)

Raise, widen match and polish exhaust port 2mm up and as wide as possible without ring gap interference

Cut away in bottom of intake side of piston for more flow during 360° duration.

Smooth out the whole intake tract and run .03mm carbon reeds.

Get squish to ~1-1.2mm

Port timing would be about:

156 exhaust duration.

110 transfer duration.

360° intake duration

104° boost port duration

23° (21.7%) blowdown

That combined with a boss pipe and 15 sha clone.

Clutches Relined with McMaster Carr high friction material bonded with pliobond, likely 30lb 1st and 25lb 2nd springs. Stock gearing. 50/50 in mind.

My goals are for mid-high range power with roughly 5k engagement of 1st and second shift about 20-25mph

Am I even in the right ballpark? Anyone have any suggestions that may help me out?

Re: Stock a35 modding.

Sounds good to me but I would choose anything over a boss pipe. Even a biturbo. A estoril would probably be the best.

Re: Stock a35 modding.

Biturbo and a real sha with the right gearing you should be capable of what you seek. I only did a little intake and exhaust porting. I widened the exhaust about .5mm on each side and changed the profile of it to be more oval and have as smooth of transition as possible, then polished it to a shine. The intake port I left rough to help with fuel atomization. I did not do anything to the piston nor did I add a spacer to the base. I had a solid 45mph bike. I also had the stubby intake for a steady shot of fuel.

I am about to do the same to my targa cyl but I do plan on opening up the piston window this time, I may also look into the spacer this time.

Re: Stock a35 modding.

Sweet deal, thanks guys. Aside from the base spacer and some parts that were missing, I’m just running with what I got on hand. I haven’t ordered a spacer yet, that idea came up today, I could always stack base gaskets but 1mm is a bit thick. Got this bike in a deal of 4 rollers in various states of disrepair. It’ll be the first one to see the light of day again. I like tinkering and I wanna make it a bit more fun for the kid I’m selling it to.

Threw a boss in one of my treats orders because I was bored, it was cheap and I thought it’d be a good idea on a v1 lol. I figured I’m stuck with it, so may as well use it. For the sha clone I had a gift card to amazon I had to burn up, so I grabbed that and a phbg clone for shits that’s still in China. It’s actually pretty fair quality for 18$. Takes dell jets without tapping and everything looks “ok”. I got the side sweep intake for it because I really hate dropping tomos motors when playing with jetting and cleaning carbs lol. I got a straight shooter too but I’ll probably save that for another time.

Re: Stock a35 modding.

Boss pipe doesn't have much low end you're better off getting an estoril. Much more power all around and very capable of hitting 50mph (edited)

Re: Stock a35 modding.

Just curious about spacing. I have ported quite a few A35 kits and never spaced them. Is the squish really that off or is your kit not clearing the ports? Because if everything is open at BDC I would not worry about spacing it. You will still have a drastic improvement with the porting you are talking about.

Re: Stock a35 modding.

> EH FCC of the QCB Wrote:

> -------------------------------------------------------

> Just curious about spacing. I have ported quite a few A35 kits and

> never spaced them. Is the squish really that off or is your kit not

> clearing the ports? Because if everything is open at BDC I would not

> worry about spacing it. You will still have a drastic improvement with

> the porting you are talking about.

Now thinking about it I agree with the not needing to space it. As wouldnt spacing it just increase the squish between the piston and head? Unless you are planning to deck the top of the cylinder down that 1mm.

Not to poo poo on your amazon purchase but you can search clone sha/bing/phbg on here and see how much trouble other folks have with them. End up getting a real one, slapping it on and all problems go away. Sometimes they are ok, but it is a real crapshoot.

Re: Stock a35 modding.

> Jay Rivett Wrote:

> -------------------------------------------------------

> > EH FCC of the QCB Wrote:

>

> > -------------------------------------------------------

>

> > Just curious about spacing. I have ported quite a few A35 kits and

>

> > never spaced them. Is the squish really that off or is your kit not

>

> > clearing the ports? Because if everything is open at BDC I would not

>

> > worry about spacing it. You will still have a drastic improvement

> with

>

> > the porting you are talking about.

>

> Now thinking about it I agree with the not needing to space it. As

> wouldnt spacing it just increase the squish between the piston and head?

> Unless you are planning to deck the top of the cylinder down that 1mm.

>

> Not to poo poo on your amazon purchase but you can search clone

> sha/bing/phbg on here and see how much trouble other folks have with

> them. End up getting a real one, slapping it on and all problems go

> away. Sometimes they are ok, but it is a real crapshoot.

Spacer is purely for change of transfer duration to bring rpms up without narrowing the power band too much. I’m not at the garage so I’m just going off internet numbers right now from someone else’s port map. I believe the transfer floors hang a few mm below bdc and I can lower the floor of the exhaust and deck the cylinder. I just don’t trust myself raising the transfer ports yet even with the right tooling.

Yeah I read up on the clones before buying them, most of the sha clones seem halfway decent. I don’t see any obvious issues so I’m gonna give it a shot. For 18$ I atleast got a doohickey or 2 off of it I can use as spare sha parts. If it’s a pain in the ass I’ll just bore the real 14.12 to 14.14. The phbg is more out of curiosity than anything else. I don’t even have a use for that yet lol.

Re: Stock a35 modding.

You can always cut the boss at the belly, then add 4-5inches of a larger belly. Wayyyyy more power

Re: Stock a35 modding.

> Yeah I read up on the clones before buying them, most of the sha clones

> s seem halfway decent. I don’t see any obvious issues so I’m gonna give

> it a shot. For 18$ I atleast got a doohickey or 2 off of it I can use as

> spare sha parts. If it’s a pain in the ass I’ll just bore the real 14.12

> to 14.14. The phbg is more out of curiosity than anything else. I don’t

> even have a use for that yet lol.

I dunno, I had the same idea about the clones and using parts off them for my Dellorto’s (I use a 15.15 on my mile build and a PHBG 20 on the beefier build). In both cases I found that the Dellortos rarely leaked and were made from strong metal where the clones just didn’t fit right in places and ALWAYS leaked, either immediately or soon after. I only had a few though, so maybe it’s just manufacturing errors?

Anyway, I’ve got a bunch of 14.12 and parts for them laying around so PM me if you’re in need

Re: Stock a35 modding.

Yeah I've been running clones for years, they might take a lil messing around But I've never met one i couldn't get working. I like the Sha with the tuning screw, better than a real one.

Sometimes you'll end up with something that's just totally wacko garbage but I have aliexpress sellers that I know send out a consistent product and I continue to buy them.

I hear people say 'drill out the sha', I used to do it but it's way more work to get that running good than reworking a clone.

Re: Stock a35 modding.

> JBOT Admin Wrote:

> -------------------------------------------------------

> You can always cut the boss at the belly, then add 4-5inches of a larger

> belly. Wayyyyy more power

Intriguing. I’m surprised I’ve not heard of this yet. Do you have to do anything with the header at that point?

> Graham Motzing Wrote:

> -------------------------------------------------------

> Yeah I've been running clones for years, they might take a lil messing

> around But I've never met one i couldn't get working. I like the Sha

> with the tuning screw, better than a real one.

>

> Sometimes you'll end up with something that's just totally wacko garbage

> but I have aliexpress sellers that I know send out a consistent product

> and I continue to buy them.

>

> I hear people say 'drill out the sha', I used to do it but it's way more

> work to get that running good than reworking a clone.

That’s what I figured. It’s probably a 80-90% chance on getting a workable sha clone. This one had solid reviews, some from tomos users. I’d love to try the Dakar one with the tuning screw, I couldn’t find one on amazon, I might scoop that next treats order and try it on my v1.

From the looks of it boring a carb is tedious. Still something I wanna give a shot one day But I think I can make this one work. Time will tell!

Re: Stock a35 modding.

Overpriced Parts /

All I did on my A35 revival was to add a bullet pipe, black and cap screen filter, 61 jet, 24 tooth rear sprocket and I got 44 mph with good takeoff and that’s with a heavy bike and my 200 pounds sitting on it,

C4385E9A-30AF-42C5-8641-D3D55575999B.jpeg

Let me know if you do all this work you’re talking about and you get close to that mph because it only took me a few hours and Less then 100$ bucks to accomplish a fast good tuned bike and it had 8700 Original miles on it before I tuned it then I put another 2000 miles on it before I sold it.

I probably should’ve kept it but A unbeliever took it for a spin and gave me $100 more than I was asking for it,

Re: Stock a35 modding.

No, just might have to change the mount to frame location. But it will give you real decent power.

Re: Stock a35 modding.

> Overpriced Parts Wrote:

> -------------------------------------------------------

> All I did on my A35 revival was to add a bullet pipe, black and cap

> screen filter, 61 jet, 24 tooth rear sprocket and I got 44 mph with good

> takeoff and that’s with a heavy bike and my 200 pounds sitting on it,

>

> Let me know if you do all this work you’re talking about and you get

> close to that mph because it only took me a few hours and Less then 100$

> bucks to accomplish a fast good tuned bike and it had 8700 Original

> miles on it before I tuned it then I put another 2000 miles on it before

> I sold it.

>

> I probably should’ve kept it but A unbeliever took it for a spin and

> gave me $100 more than I was asking for it,

I could go the easy route and just slap some bolt ons on it, but I wanna play with transfer timing and the a35 cylinder has always interested me the most of stock cylinders for porting. It’s got big potential. Steel takes longer to cut than aluminum but I just matched and raised the exhaust on a puch hi torque cylinder it wasn’t all that bad. It’s only gonna cost me a base spacer and the sha clone on top of everything else the bike already needed. I work at a machine shop so decking is free. Should be into the whole thing less than 400 including the stuff I already had on hand. He’s also talking about a kit and jammer, so I may get this cylinder and first clutch back if he thinks a kit will be faster.

This bike was loved a bit too hard, so it needs a bit to save it. Both clutches show signs of being shredded and relined, 1st gear was cooked and the cork peeled off of 2nd like a sticker lol. Sprag clip was no where to be found, right side pedal and crank arm were missing, left side was “converted” to kick start, complete top end was in a box amongst others, several clutch cover bolts missing, reeds were iffy at best, crusty stock exhaust etc. if it shreds a crank and it’s my fault, I got a clean a55 crank and case I’ll throw him to put his trans guts in.

I think I’m just a glutton for punishment, the first moped engine I rebuilt was a Za50. Still have yet to crack an e50. Replaced every bearing and the pucks in the case and put a stuffed crank in it paired to the treats reed kit, countersunk head, vm20, 4 petal and treats pipe. Stock clutches flipped second. Matched throughout with a big ole window cut in a single ring piston widened and raised exhaust for 160° duration. 20/35 gearing on that hitting 55 with me at 200lbs, can probably push it further than that and will. So I’m gonna gear up again to 21/35 or 22/35 whatever it’ll handle, to keep the revs down and shit from exploding in the trans case.

If nothing else comes up tomorrow I’ll be getting the clutches done and some intake and exhaust work atleast. Probably gonna slap it together and try it out before the spacer. The spacer is essentially just to move the power up and get as much as I can out of this dinky boss. If he wants to throw a better hi rpm pipe on it that’s when the change in port timing will really shine.

Re: Stock a35 modding.

> JBOT Admin Wrote:

> -------------------------------------------------------

> No, just might have to change the mount to frame location. But it will

> give you real decent power.

I may give that a shot on the puch boss I got. The bike it’s on is a ratty buddy bike, so with my welding skills it’ll flow perfect.

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