hobbit bogging out and dying

ok guys, one more problem i seem to be experiencing on my pa50. I installed a proma pipe yesterday, and it run fairly good, gained about 4mph, but it gets me those 4mph much faster than before which is perfect for around town... obviously i'd like the other 4 that they claim I can get but i'll settle for now unless you guys have tips for tuning. anyways, my problem is that when i'm on regular fuel intake, it dies after a quarter mile, but then i switch it to reserve, and start it back up, it runs great, borderline better than it does before. problem obviously is that I would eventually run out of gas. did i do something wrong when installing the pipe? any help in the right direction would be great, as i've said in other posts, i'm very new to mopeds and just learning a lot already. thanks!

Re: hobbit bogging out and dying

go with that 80-81 jet instead of the 78 for a lil more umph with that pipe....also it sounds like you are using all the fuel in the carb faster than it can refill is my guess....when you sit a minute it refills slowly.... have you pulled the petcock off and cleaned the petcock and filter screen etc and checked for good flow?

Re: hobbit bogging out and dying

Adam Lohner Wrote:

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> obviously i'd like the other 4 that they claim

Your results may vary - Nobody claims 8mph. Especially the company, so don't blame the pipe.

On your hobbit - the petcock pickup is dirty, Or your carburetor float level is set too low. Thats good because they are both easy fixes, readily available, and very affordable.

New petcock $10-15 or clean your existing. ~10-15min to unbolt, drain and shake out the tank with some gas to make sure its clean, and replace the tank.

To fix the carburetor takes more time, but it costs nothing unless you wish to replace a gasket or a needle. Your float is blackplastic so it should not be cracked unless its a manufacture defect. In either case < $10-15 and a few hours time if you haven't spliced open your hobbit and subframe before.

while your in your carburetor you might as well throw the size 80 jet in as suggested by monti. Info on how to acquire the jet from Boats.net is in the wiki (pa50 parts page), or find it locally at a Honda lawncare facility.

Next mod after you settle that up is to Notch the variator and gain a few mph's with some different weights.

___

First thing I would do, clean the screen on your petcock today, if that fixes it - good! Then order up a jet and get some rollers. Then next week if you get parts, splice it open and fix the carburetor or just install the jet, and notch it.

<<--edit-->>

Oah yeah, you will want a pa50ii ramp plate ( not the variator, they are the same as the pa50i ) if your going to notch and see good results

<<--endedit-->> (edited)

Re: hobbit bogging out and dying

Emil Kniemel /

related, running a notched variator right now and i cant seem to get it to variate past the unnotched amount while under load. (variates completely out on the stand, off the stand same MPH as unnotched) the longest flat straight ive found for testing is ~0.4 miles.

tips koz? running graham's oversized rollers.

Re: hobbit bogging out and dying

I think you need to go lighter and drill out your precious rollers Emil. Not sure though! I'm not great at kitting or tuning the vario ;P I just blow stuff up and make things more difficult.

Re: hobbit bogging out and dying

Emil Kniemel /

even lighter, eh? i have two sets of weights so i guess i could drill 'em.

i know your thread, its my favorite-- real talk.

back to your regularly scheduled programming..

Re: hobbit bogging out and dying

Gruff "(OFMC)" - /

Adam you may also want to open your air intake with a FF filter.

just for conversation purpose... wouldnt you want heavier weights if it wasnt variating all the way? I mean why would less make it variate more?

Re: hobbit bogging out and dying

Emil Kniemel /

Gruff - Wrote:

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> just for conversation purpose... wouldnt you want

> heavier weights if it wasnt variating all the way?

> I mean why would less make it variate more?

honestly, thats what i thought.

Re: hobbit bogging out and dying

[Radium City] kyle k $ /

when you are under load and it not variating all the way how long are u riding it? it can take quite a while for it to go completely closed. as for the lighter weights he does have a point. too heavy of weights can make it variate too quickly thus taking u out of pipe powerband. when it variates the rpms will drop considerably so if it is too early the it takes that much longer for it to catch up and and take advantage of that notching. of course it will variate all the way with no load...there's no resistance of ur 150-200 lb fat self on that back wheel!

Re: hobbit bogging out and dying

[Radium City] kyle k $ /

oh sorry you said .4 miles, try to go longer and it will eventually catch up with you.

Re: hobbit bogging out and dying

I've been curious as to what it really means to "variate fully"

This schematic is from the manual, and it looks like it's to scale, including the belt being 2mm below the lip of the rear pulley:

I don't know the actual dimensions of the vario, but with a little photoshop, I estimate that the belt is at "rest" at ~57% of the vario radius (Note that when the belt is at rest, there's a little gap between it and the shaft of the drive face). When it is fully variated, the belt rides at ~91% of the radius.

Next is my variator on the stand:

Using the same method, my belt is at rest at 54% of the radius, and rides at 83% of the radius at full variation. I strongly suspect that I'm not variating fully, though I'm not quite sure why. Maybe it's where my belt should be riding at rest?

Someone who KNOWS their variator operates perfectly, please post pics of it at rest and fully closed, and I'll run my numbers on them, too.

Re: hobbit bogging out and dying

Emil Kniemel /

dont have a pic at the moment, and my notched variator on the stand, can variate so far as the belt rides above the variator ever so slightly.

unnotched, it would variate about the same as yours, maybe a little more.

if the pic is to scale, blow it up to the same size as your photo, and then lighten the opacity to overlay it on your photo to see how much more yours should variate?

Re: hobbit bogging out and dying

[Radium City] kyle k $ /

heres how my notched one goes. see how the belt rides as high as it can? that would be full variation, mine i guess could go another mm or so but whatev

photo.JPG

Re: hobbit bogging out and dying

Kyle, your notched variator looks like it's riding about 99% of the way out at full variation. The picture in the wiki looks like it can go a little bit further, or at 103% of the radius:

Do you tighten that big nut outside the movable face with the belt on or before you put the belt on?

Re: hobbit bogging out and dying

[Radium City] kyle k $ /

idk probably before I put it back on. yea I see that urs is peeking out slightly over the top but it's pretty minimal in comparison. I can't complain about speeds I'm getting tho that little bit isnt gonna blast me too much harder. looks like that's not the stock belt either, I have a replaced stock belt. could be a reason also possibly

Re: hobbit bogging out and dying

[Radium City] kyle k $ /

I'll get out my big boy camera and a helper to rev while I get some high shutter speed shots from the same angle. i thinks it's just the angle I shot

Re: hobbit bogging out and dying

Made a few discoveries...

I've been installing the belt incorrectly. Though I'm not the smartest person in the world, I wonder how many other hobbit owners do this.

DO install the movable face, ramp plate, washer and nut WITH THE BELT OFF.

DO loosen the rear wheel assy. in order to get the belt on the bike.

DO NOT install the belt with the movable face off.

DO NOT tighten the vario nut while the belt is installed.

I had been doing the latter since it was easier to get the belt on. At rest, the belt is NOT supposed to rest directly on the drive face shaft, but a little bit above it in the vario "V"

This increased my stock variation from 83% to 90%, seen in the picture below (top is before, bottom is after):

Added ~ 3 mph top speed, and improves acceleration a little since it starts off in a better gear. I guess now's the time to notch it!

Re: hobbit bogging out and dying

Emil Kniemel /

Hmm. Time to reinstall my variator.

Re: hobbit bogging out and dying

It should be noted that if you weren't getting full variation due to the belt being pulled too tightly then you were adding undue friction and side load to the crankshaft. The combination of the two will affect gearing top to bottom and top speed due to parasitic loss. But, if it was because the ramp plate was simply not as close to the centerline of the two faces as it should be (due to being tightened down on the belt) then it would be loose once the belt had been allowed to move and take the pressure off the nut. I'd be surprised if you didn't lose the nut entirely due to being loose or eat the flat sides off the center of the ramp plate in that case from backlash.

Re: hobbit bogging out and dying

Emil Kniemel /

I reinstalled my variator anyway. I've always kept the front of the belt loose when reinstalling anyway though (by creating slack by squeezing the belt at the rear end to open up te variator). We'll see tomorrow. I'd also like to add that if you're having trouble reinstalling the belt after the variator is tightened down, you can also remOve the entire clutch assembly then put the belt over the front variator then everything back on.

Re: hobbit bogging out and dying

Ryan Rossler Wrote:

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> It should be noted that if you weren't getting

> full variation due to the belt being pulled too

> tightly then you were adding undue friction and

> side load to the crankshaft. The combination of

> the two will affect gearing top to bottom and top

> speed due to parasitic loss. But, if it was

> because the ramp plate was simply not as close to

> the centerline of the two faces as it should be

> (due to being tightened down on the belt) then it

> would be loose once the belt had been allowed to

> move and take the pressure off the nut. I'd be

> surprised if you didn't lose the nut entirely due

> to being loose or eat the flat sides off the

> center of the ramp plate in that case from

> backlash.

The last bit is exactly what happened to me. The bent locking washer does a good job of keeping the nut on regardless of how tight it is, but I was getting a ton of backlash and eating into the "ribs" that the plastic guides ride on.

When that happened, I wound up just filing them even. Nobody seemed to know why some people have this problem and others don't even need the guides. Maybe this is it.

Re: hobbit bogging out and dying

Emil Kniemel /

after tightening down the front, and then installing the belt, my acceleration is smoother at the bottom and i did gain some top speed. when i was hitting < 41mph on this smallish straight, i finally hit 42mph. can't wait to try it out on a looonnnnggggg stretch.

Re: hobbit bogging out and dying

On a stock unported cylinder with a Proma that is damn good. Most get high 30s, I got 39-40 depending on grade and wind. Obviously the notching helped, but do not go lighter on the weights.. Just from reading through the misinformation above it needed to be cleared up. It takes more mass to force the variator into the notched area. I notched and tried to run mopedfactory weights in mine with just the pipe and it would go full range on the stand because it could build up the rpm required to give the lighter weights the oomph to do it but on the road the bike didn't have the power to hit that rpm. The stocks weights, although they accelerated the bike slightly slower, got me full range on the vario and got the top speed that it was notched to achieve in the first place.

Re: hobbit bogging out and dying

Colin McC Wrote:

> The last bit is exactly what happened to me. The

> bent locking washer does a good job of keeping the

> nut on regardless of how tight it is, but I was

> getting a ton of backlash and eating into the

> "ribs" that the plastic guides ride on.

>

> When that happened, I wound up just filing them

> even. Nobody seemed to know why some people have

> this problem and others don't even need the

> guides. Maybe this is it.

I wasn't really referring to the area that the guides ride on as much as I was talking about the two flat faces that the ramp plate uses to index itself on the hub. they have some slop and with a loose nut would slam back and forth until they rounded out and the pulley just spup. However I suppose the increased force of impacting back and forth could damage the guides as you mentioned, but being plastic that is kind of what they are intended to prevent entirely.

Re: hobbit bogging out and dying

Sorry about the weight misinformation, I have only run a hobbit on a stock cyl w/ pipe and it was a bad time

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