Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

so ill start off with a facebook video of me riding and im new to repairing mopeds but i've tinkered in the field of motocycles and scooters , you can hear the bogging at take off.

as for details , my targa lx 2002 is kitted to 70cc and a unknown carb(for now) ill check tomorrow . with a 85 main jet . has a A35 chrome bullet for the exhaust. now what i've done so far was

. Taking off transmission side cover and replacing the clutch pads , both 1st and 2nd are now brand new

. i made sure all shims are in place 2 on the left 1 thick small in the middle , and one behind the clutch.

.i changed my spark plug as well .

.cleaned out the carb multiple times all jets were clear.

i did notice that there is a leak on the magneto side of the bike , i havent changed the seal yet but will try tomorrow after a rebuild. the oil i placed in was no where near when it came out the drain , its as if my engine just swallowed it , missing a good 6-8oz of oil , and it was changed today lol . im not sure whats causing the bogging but the bike was fine this morning , rode from 9am-11am , then it crapped out , this happend a few days ago too when i thought it was the clutch since the pads were gone. if anyone can help me that would be amazing , if i missed anything please do ask ill try to provide all the info i can.

PS: transmission side has all teeth but one.

IMG_1070.jpg

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

Re: Bogging on 1st gear ? i tried everything ! :(

Sounds like your flyside seal is bad. Replace it and the other side in the gearbox too.

Re: Bogging on 1st gear ? i tried everything ! :(

Sounds like you are leaking through the seals when it gets warmed up, time to replace them especially given all the other repairs you’ve done. Inspect/replace top end gaskets too if possible. Worth it in the long run, and replace the bad gear ASAP

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

I’ll check the seals later on today and will post my results, I had bought some awhile back that are still new so I’ll replace them when i take the thing apart , that might just be my issue hopefully lol , I’ll check back with you guys later on thanks for replying

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

Ok update , I did a complete ducking *quack* rebuild and same issue , so I’m guessing it’s either the top end (I didn’t take the top end apart) . And now that I think about , when I give it power the bogging sound does come from the top end , maybe the gasket I placed in is faulty ? And when I first took the top end off there was no gasket between the piston and the top part so I placed one there. The carb was also soaked in carb cleaner and cleaned thoroughly looks almost new lol . Changed all seals and still nothing . At least my sprocket side won’t leak oil anymore

Re: Bogging on 1st gear ? i tried everything ! :(

How did you do a complete rebuild without taking the top end off?

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

Sorry I did a half ass rebuild lol , Im taking off the top end tomorrow , I really think my issue is the gaskets up front

Re: Bogging on 1st gear ? i tried everything ! :(

So it wasnt a complete re build... I'm kind of at a loss here, you really should get a manual. Possibly try doing some research. Tomos are one of the most well documented mopeds.

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

That makes two of us lol, I’ve even asked a moped shop near where I live and they are confused too as to what’s going on with my bike , I’m calling it out right now that it’s my front end gaskets, the bogging sound seems to come from the exhaust,

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

heres some more pictures as well, i had a video but i cant post a video here

56457819_810886589291516_1496346213421678592_n.jpg
56547296_1267444660070001_3938246137235898368_n.jpg
56563272_1033389413523142_4135012637903683584_n.jpg

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

and the last 2 pics , at least my oil leak is gone ...

56726544_802921050106445_6436708070214074368_n.jpg
56905097_1032508446948637_5323187852551389184_n.jpg

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

Re: Bogging on 1st gear ? i tried everything ! :(

Brandon Weiss (Detective brandon to you) /

That's not bogging, that sounds like 4 stroking. You are jetted too rich, or you have an air restriction somewhere.

Have you also verified your timing is correct?

Re: Bogging on 1st gear ? i tried everything ! :(

Dirty30 Dillon /

The seal you put behind the clutches is in backwards, which probably won't cause your problem, but is not good practice either way.

It's definitely four-stroking which is just a tuning issue. I don't think you're going to solve anything by re-gasketing he top end and it certainly is not an issue with the transmission.

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

so i found something new today , the port where the exhaust pipe connects to the head has a leak , i can see oil seeping out , and after i checked all over for leaks and i torqued the bolts , my rear wheel stopped spinning on idle , also changed my air filter as the old one completely busted into pieces. theoretically would a small leak in the exhaust port cause the engine to struggle at 1st gear ? as for the timing im waiting for the puller. and as for the seal , it was weird because both sides look like that lol. actually its dual lipped

https://www.treatland.tv/tomos-A3-A35-A55-engine-seals-GREEN-set-p/tomos-seal-green-set.htm

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

also i think my bolt is either ducked or the threading on the top end is screwed. i couldn't fine a replacement on treats. if anyone could send me the link that would be awesome, as for the leak , is it possible to use this for the exhaust port ?

http://www.amazon.com/dp/B0002UEN1U/

please bare with me im super new to mopeds lol im just trying to fix what i can

Re: Bogging on 1st gear ? i tried everything ! :(

No. No RTV of any kind anywhere near a moped. Ever. You're doing everything wrong so far. My best advice to you is put down the wrenches, and spend a solid month READING AND LEARNING how mopeds, and two stroke motors work. Then pick up your tools. I'm not being rude here, but you are asking the wrong questions, and not understanding people's answers at all. Educate yourself. There is so much information you need to learn, and you can find it all on this site. READ READ READ.

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

if im doing everything wrong then i guess what others are telling me is wrong too , not trying to be a dick either , but i did do my research , i may be missing things like "dont use rtv" but i successfully placed everything correctly and made sure i used the right gaskets for every section on my moped. all i really have is a leak at the exhaust port and i need to tune my carb properly and check my timing

Re: Bogging on 1st gear ? i tried everything ! :(

what carb?

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

The carb that was installed when first bought was a PHVA DS, the main jet is a 85 , I didn’t buy this part , came with the bike when I first got it , it’s been cleaned out about 4 times

Re: Bogging on 1st gear ? i tried everything ! :(

85 is a massive jet in a 14 Phva. Try a 64-75 jets and report back. If its the 17 Phva I'm not sure on jetting, sometimes a bigger carb requires a smaller jet. On this ciao I was working on yesterday i went from a 12/10 to a 12/12 and had to down jet. The difference between a lean bog and a rich bog is pretty audible. A rich bog will change tones completely as it takes 2 full rotations of the crankshaft to expel the gases. A lean bog will sound more or less the same as normal, but a little more hoarse or if it is really lean want to stall out completely. A magneto side seal leak will also behave rich or cause a bike to have a stutter from the loss of case pressure. Did you replace the right side crank shaft seal as well?

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

It’s the 17 phva and I did replace all the seals but the magneto seal as I’m still waiting for the puller to arrive. Seems like either the jet is giving me issue or there’s still a leak some where I’ll try jetting differently

Re: Bogging on 1st gear ? i tried everything ! :(

Dirty30 Dillon /

> Daniel '' Wrote:

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

> Sometimes a bigger carb requires a smaller jet.

Sage advice that I think many don't realize for a long time.

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

> Dirty30 Dillon Wrote:

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

> > Daniel '' Wrote:

>

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

>

> > Sometimes a bigger carb requires a smaller jet.

>

> Sage advice that I think many don't realize for a long time.

I’ll be getting some jets from my local moped shop tomorrow and I’ll give that a try , by stock it comes with a 85 and when I got the bike the first time it had a whole lot of air leaks and now that it’s all cleared up except the exhaust port , the jet might need to be adjusted, Also as for my question , would a small leak at the exhaust port cause performance issues ?

Re: Bogging on 1st gear ? i tried everything ! :(

Brandon Weiss (Detective brandon to you) /

> Anthony Vargas Wrote:

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

> > Dirty30 Dillon Wrote:

>

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

>

> > > Daniel '' Wrote:

>

> >

>

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

>

> >

>

> > > Sometimes a bigger carb requires a smaller jet.

>

> >

>

> > Sage advice that I think many don't realize for a long time.

>

> I’ll be getting some jets from my local moped shop tomorrow and I’ll

> give that a try , by stock it comes with a 85 and when I got the bike

> the first time it had a whole lot of air leaks and now that it’s all

> cleared up except the exhaust port , the jet might need to be adjusted,

> Also as for my question , would a small leak at the exhaust port cause

> performance issues ?

It would not cause the issues you seem to be having, no.

If you have the stock cylinder and stock exhaust, an 85 jet is too large by far. In addition, a 17.5mm carb will not perform better than a 14mm if you have a 14mm intake still.

I have a lot of experience with the 14 and 17.5 PHVA, and an 85 main jet is usually a solid starting point for a 65-70cc kit with an exhaust. Idle jets between 32-38 usually.

With the stock cylinder and an exhaust, you would likely find yourself anywhere from the high 60's to low-mid 70's main jet.

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

Alright so I forgot to mention that I’m not running stock , this bike came with a 70cc kit and a biturbo that I removed and used a chrome bullet instead , seems like my issue might just be the carb that’s not adjusted properly, or a leak on the magneto side seal , I know for a fact that my lx was running fine and then out of no where, the bogging started happening which is weird and unexpected.

Re: Bogging on 1st gear ? i tried everything ! :(

Brandon Weiss (Detective brandon to you) /

> Anthony Vargas Wrote:

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

> Alright so I forgot to mention that I’m not running stock , this bike

> came with a 70cc kit and a biturbo that I removed and used a chrome

> bullet instead , seems like my issue might just be the carb that’s not

> adjusted properly, or a leak on the magneto side seal , I know for a

> fact that my lx was running fine and then out of no where, the bogging

> started happening which is weird and unexpected.

When I said that an exhaust leak typically would not cause running issues, I was referring to slight leaks. A large leak at the flange could cause issues, but I doubt that is your problem in this case.

Given the fact that your jetting is not way off, or at least not as far off as originally thought, I would replace the magneto side seal before you continue. Be certain you reinstall the stator plate exactly where it came from, and that you do not lose the flywheel pin/key. When you remove the magneto side cover, look for oily liquid seepage, which would be indicative of a bad leak.

And remember when replacing seals, the hollow side should face the pressurized side of things. (Given that logic, I never understood why the clutch side seal faces the transmission instead of the crankcase on an e50 though)

Re: Bogging on 1st gear ? i tried everything ! :(

Anthony Vargas /

> Brandon Weiss (Detective brandon to you) Wrote:

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

> > Anthony Vargas Wrote:

>

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

>

> > Alright so I forgot to mention that I’m not running stock , this bike

>

> > came with a 70cc kit and a biturbo that I removed and used a chrome

>

> > bullet instead , seems like my issue might just be the carb that’s not

>

> > adjusted properly, or a leak on the magneto side seal , I know for a

>

> > fact that my lx was running fine and then out of no where, the bogging

>

> > started happening which is weird and unexpected.

>

> When I said that an exhaust leak typically would not cause running

> issues, I was referring to slight leaks. A large leak at the flange

> could cause issues, but I doubt that is your problem in this case.

>

> Given the fact that your jetting is not way off, or at least not as far

> off as originally thought, I would replace the magneto side seal before

> you continue. Be certain you reinstall the stator plate exactly where it

> came from, and that you do not lose the flywheel pin/key. When you

> remove the magneto side cover, look for oily liquid seepage, which would

> be indicative of a bad leak.

>

> And remember when replacing seals, the hollow side should face the

> pressurized side of things. (Given that logic, I never understood why

> the clutch side seal faces the transmission instead of the crankcase on

> an e50 though)

Wow guys I found my issue , so before my bike had so many air leaks and I guess after I finally fixed all of that my air mixture screw was turned in all the way , I adjusted my idle screw and air mixture screw to get it perfect and guess what ... no more bogging , I took it out for a spin. For 30-45 min and everything sounds great , I might need a new spark plug cause my current one looks fouled . Thanks for all the help guys I really appreciate it ! Time to rip !!!

Re: Bogging on 1st gear ? i tried everything ! :(

Brandon Weiss (Detective brandon to you) /

Great! Odd though, typically if the idle screw is set so far rich that you 4 stroke like that, the bike would usually not idle, so something as simple as that did not come to mind.

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