Yet another Reason AV7's can't go fast.

So during a sick moped monday ride last night, i held open throttle (or close to) for over several miles pushing a slow bike up a canyon pass, on my yellow moby, then later that night held a solid full speed for several more miles, all in dark foggy conditions.

I must say i am very proud of my little bike since it tends to break alot if i push it.

however it made it through the night with a great sounding smooth fast ride except of one thing, my magneto sheared from the center section where the magneto nut holds it to the crank, right at the end of the ride, luckly it didn't shear off completely and i was able to ride the last mile home.

I am using av7 points, stator, and magneto on an av10 engine.

the old av7 parts can't hang with high speed extended runs around 50mph.

yet another reason, the AV7 just can't hang with the big dogs.

and another reason to convert to the av10 setup, as well as upgrade all stock av7 components to av10 performance equipment if ur building for speed on a moby. as peter put it "go big or go home" or in my case, go big then go home and fix it.

camera phone sry

you can see the little dimple also broke right off.

doubt this will help anyone any where, and to the magnetos defence it did hold up for months b4 this happened, also i do ride my bike everyday, rather hard, so that could also have somthing to do with it.

i'm curious how long the clutch pullys will last as well as the er3's

just installed a new clutch pully with the stock variator and clutch, i got 2 clutches biatches lol, more on that wen i get a better camera

Re: Yet another Reason AV7's can't go fast.

Are you sayin that trashes the crank everytime it happens?

Re: Yet another Reason AV7's can't go fast.

oh snap! (pun intended)

i just lost the 2nd sleeve which the bolts that hold the ER2 together slide in when it variates. I'm pissed!

gotta make some new ones i guess, no way replacements will be here by SacTOWN.

Re: Yet another Reason AV7's can't go fast.

well, as you know...this helps me out! i'm trying to win maitlands bid on the AV10 he has for sale! yay for case induction! boo to the A35 engine!

Re: Yet another Reason AV7's can't go fast.

the crank is fine, just the things attached to it seem to break these days.

things that shear off on my moby:

first it was the av7 cranks, upgraded to the av10

then it was the av7 clutches got a clutch pully, (er3 on the way)

now its the av7 magneto, gonna have to get my cdi working again i guess . naw i'm just gonna replace it with one of the tonnes of av7 mag cover i got round here and hope it lasts anther 4 months

peter er2 down, already!!!! fix b4 sac man, i don't want to see u on a loaner.

Re: Yet another Reason AV7's can't go fast.

🇮🇹💦 Of the Loin /

also, av7 engine springs are not good with ANY performance variator.

get doppler spring ASAP people/

Re: Yet another Reason AV7's can't go fast.

i pulled a serious maguiver today and fixed the shit out of my ER2, its pretty much invincible now!

Re: Yet another Reason AV7's can't go fast.

i think i am figuring out how to build a sick moby up without buying all the parts in one expensive bundle.

so far i think a good layaway moby build goes in these steps:

1. 15:15 dellorto

2. le sweet french pipe

3. av10 (thats a given) w/cdi

4. clutch pully (given ur av10 did not have a kick start otherwise variator here and clutch pully at #6)

5. top end kit

6. performance variator

7. doppler spring

8. polini 4 pedal reed cage, and 21mm dellorto

9. engine rebuild with a performance crank, and polini bottom end.

at 8 and 9 it becomes hazy i think, you could go polini bottom or not, race crank is probably a good idea in the long run, i think its going to be my next investment.

you could ride at all the steps for a good while (at the least a month between some) till upgrading to the next part. giving the moby maniac on a budget some time to save up for the big guns

obviously this is a crude list lol

Re: Yet another Reason AV7's can't go fast.

🇮🇹💦 Of the Loin /

Im at step 6. Im jumping 7 and getting a 19mm intake cuz i got a 19mm phbg in a trade

but yeah that sounds dead on elliot

Re: Yet another Reason AV7's can't go fast.

elliot, as soon as the snow flies i'm copying the doppler spring and selling it as my own. I started this project in the spring but didnt get as far as i wanted. I will most likely have the two metal brackets lasercut at school. Its gonna be so so rad.

how does $50 for a doppler spring clone sound?

Re: Yet another Reason AV7's can't go fast.

pretty good as long as that stuff holds up, you should talk to Dan 1977 about gettin them in his shop, he is really gonna try and push more french stuff once he gets situated in SF

o i can't wait to put my doppler spring on, i love the red, i put it on b4 i had a kit and the stock variator couldn't even pully it. waitin on the er3 to mount that sucker on.

Re: Yet another Reason AV7's can't go fast.

Good to know. I was gonna snag an AV10 and throw the AV7 magneto on it to keep all the electrical working. Now I know Ill just have to wait to build up a race ped.

Re: Yet another Reason AV7's can't go fast.

🇮🇹💦 Of the Loin /

yeah dude im stoked that when i move to the city, theres gonna be 1977 there waiting for me

viva la resistance

Re: Yet another Reason AV7's can't go fast.

id feel better replacing the bearings and seals at least before id kit it.

Re: Yet another Reason AV7's can't go fast.

This only happens to elliot. Would you get some new bearings for crying out loud!

Re: Yet another Reason AV7's can't go fast.

Think maybe there already was cracks in the flywheel because they are pretty strong items.

Do you need new bearings?

Instead of a CDI why not just get a crank trigger ignition?

Re: Yet another Reason AV7's can't go fast.

What is a crank trigger ignition? Could you post a link to buy one?

Re: Yet another Reason AV7's can't go fast.

i don't need new bearings, my engine was basically brand new when i started but yes i'd replace all that shit too if ur av10 is not "like new"

and yeah the magneto was getting warn out, i'm not going to switch to cdi netime soon

Re: Yet another Reason AV7's can't go fast.

and i will be replacing the bearings as soon as i get a race crank, o so much cash all the time, i think it can go another month without a rebuild

Re: Yet another Reason AV7's can't go fast.

http://www.jaycee-ent.com/cranktriggerignitions.html

wow, would this thing actually work on a motobecane....hmm, if i had the money, it'd be fun to play with these. seems like it'd be a good replacement for the flywheel on the right side, if it could work

Re: Yet another Reason AV7's can't go fast.

sorry, wrong link....here's the one i meant to post

http://www.rcdengineering.com/crank_trigger.html

Re: Yet another Reason AV7's can't go fast.

You can make a crank trigger with a hall effect sensor, ignition control and a different coil.

Re: Yet another Reason AV7's can't go fast.

that would be awsome!

Re: Yet another Reason AV7's can't go fast.

its not worth the effort when a CDI is readily obtainable.

Re: Yet another Reason AV7's can't go fast.

IF youre willing to replace your crank shaft

Re: Yet another Reason AV7's can't go fast.

if you're kitting your motobecane it should be considered top priority to replace your crankshaft.

Re: Yet another Reason AV7's can't go fast.

just something else for you to dream about.

Re: Yet another Reason AV7's can't go fast.

I am surprised that it would shear off, I would have thought that the cam would spin first since it is only press fit in place. This may seem like a dumb question but was the flywheel seated properly on the end of the cam? Has it ever spun around under the Novi nut? The center section must have been scored or been struck in some way first to weaken it.

I don't know why it would break like that strictly from regular use short of an unlikely imballance in that flywheel, which would show up more at low RPMS as opposed to higher RPMS, there is no load on that flywheel other then it's own weight. Anyhow it should be an easy fix, a thick washer welded to the outside of the flywheel should solve that from happening, it would be a possible upgrade.

Re: Yet another Reason AV7's can't go fast.

And what options are there for crankshafts for the AV7? Only ones Im aware of are the Doppler and the stock AV10.

Re: Yet another Reason AV7's can't go fast.

And also I cant help but ask the same question once again, could it be due to running the variator minus one ball?

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