103 bogs at RPM peak only under load?

ok,

i have been working on this 103 forever and it's been driving me insane, electrical issues, flow issues blah blah blah.(which means i now know everything is exact, new wires, good connections, new points, everything timed with a light and tools etc)

trying to tune it i can not seem to get it right and i am not sure why

i have the 70cc polini, just put into the polini cases, er3 w/o clutch and a clutch pulley.

I looped a tie down to the variator and started it without a belt to try and see how it was running without it shooting away from me, and i had no way to hold up the back wheel.

revs high as shit, sounds really good, gets going crazy amazing, no burps no nothing, perfect. and i can hold it wot for an extended period of time

when i am riding it though it climbs rpms, variator starts to variate(really light weights) (WOT) reaches a plateau for a few more MPH, climbs rpms variates some more, climbs rpms and then womp, burps, sort of misfires, runs again at lower rpms fine, can climb slowly to the same point and starts to misbehave still...

does not seem like a light seize, does not seem to be bogging, feels sort of like running out of gas, but i went over that all again and it is ok, and it only happens when belted and carrying me, not when just revving the engine like crazy...

ideas? anyone else had a gremlin like this?

right now my thoughts are still fuel maybe? i couldnt run wot when the belt was off for more than a few minutes on my street cause of neighbors, but till i stopped everything seem fine, plenty of gas up in the filter still, flowing well.

the other thing could maybe be the condenser, but only because i havent put a new one on, but it doesnt seem to be the issue anyway...

Re: 103 bogs at RPM peak only under load?

stock carb?

i have the same problem but i think mine is that my pilot jet is lean

Re: 103 bogs at RPM peak only under load?

21 dellorto

pilot jet would be up to 1/4 throttle, this is all at a specific WOT and RPM moment

Re: 103 bogs at RPM peak only under load?

yeah. mine was when i was at wot and let off and got back on it.

im a tard. excuse me.

Re: 103 bogs at RPM peak only under load?

could be the ignition coil, even the NOS ones are notorious for going bad pretty quickly. many perform poorly after they run for a while and heat up. also, could be a compression leak that is exacerbated by high rpms under a load. clean your engine, and then check the head gasket area and/or decomp plug for light colored oil after you run it. what main jet are you running? could be too lean- done any plug chops? on a final note, with all of the money you have into it, with the kit and sweet doppler shizz, get rid of the crappy ignition- buy a cdi and never think about points again!!

Re: 103 bogs at RPM peak only under load?

no air leaks, coil etc from a puch.

no cdi's available. not lean.

Re: 103 bogs at RPM peak only under load?

its the ignition i go through one about every month or use the BLACK one that treats has 18 bucks. a new condencr as well it will fix it also timing at 2.2btdc

Re: 103 bogs at RPM peak only under load?

is that ducati cdi available thru malossi direct? although with waiting for shipment more like malossi indirect..

Re: 103 bogs at RPM peak only under load?

lose some weight fatty :-p

Re: 103 bogs at RPM peak only under load?

treats will have more 103 cdi's in this week. but you can make the points work

Re: 103 bogs at RPM peak only under load?

trying to trouble shoot, not buy new things.

Re: 103 bogs at RPM peak only under load?

ciao. bring it by the shop one day. seems like an easy fix.

the magnum was doing the same thing in LA at really high RPM's. Turns out that my ignition coil went bad. Also we can look over your wiring to make sure its super duper grounded.

Re: 103 bogs at RPM peak only under load?

just got another puch coil at the shop today to put in, might switch out the high tension too

Re: 103 bogs at RPM peak only under load?

still testing, but i may not have had enough weights in my variator?

they would spin fast enough to get 3/4 out and then stick for a while and the RPMS would CLIIIMB and then(i THINK) it would start to open more and that sudden change from SPIIIIIIIIN to putting force out again as the belt was grabbed more and the spring forced back more that it would cause a weird burp bog slow down. i dunno. more riding after work.

Re: 103 bogs at RPM peak only under load?

You shouldn't ever be tuning on the stand, in my opinion. It provides very unrealistic results compared to riding. I only recommend it for initial startup tuning/idle, etc.

A little flow chart:

Are you hitting your RPM peak Y/N?

If y, increase the weight on the variator, or increase the spring tension. Preferably the latter, it's more adjustable.

If n, how do you know?

Re: 103 bogs at RPM peak only under load?

more weight seems to have fixed this

wouldnt increasing the spring tension and keeping the weights light exacerbate the problem?

how do i know when i reach peak RPM?

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