R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro On-Road

Reply
 
Thread Tools Search this Thread
Old 08-23-2010, 02:11 AM   #1
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default jumping gear

hi all, my gear jumps from 1 to 2 and 2 to 1 all the time... Is no top speed... Sounds like something blocking engine. Just wonder can be that because my engine is too lean on the bottom? Engine is mega zx .12. Car serpent 720. I just fitted there carb from nova made for mega mf.
__________________
facebook.com/rogergrafix
roger999 is offline   Reply With Quote
Old 08-23-2010, 04:14 AM   #2
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 6,271
Send a message via ICQ to Roelof
Default

Be sure to adjust the shoes of the gearbox very close to the 2nd gear housing. If the gap is to large you will get this.
__________________
The quality of an answer comes with the quality of the question.
Roelof is offline   Reply With Quote
Old 08-23-2010, 04:23 AM   #3
Tech Adept
 
gfilos's Avatar
 
Join Date: Aug 2008
Location: Greece
Posts: 230
Default

Quote:
Originally Posted by roger999 View Post
hi all, my gear jumps from 1 to 2 and 2 to 1 all the time... Is no top speed... Sounds like something blocking engine. Just wonder can be that because my engine is too lean on the bottom? Engine is mega zx .12. Car serpent 720. I just fitted there carb from nova made for mega mf.
1).check the condition of the one-way bearing
2).check the 2sp shoes and bell for excessive wear. (if shoes are worn out, you wont have a consistent change) I would change shoes and bell. Also make sure you have a minimum gap between shoes and bell without any touch between these 2.

Sometimes its about the track and when having a fast turn you have this kind of shifting (jumps to second, then back in first). If this is the case, i would try to make shifting a little earlier so you can pass the turn with 2nd gear. If this happens at the straight, then something is wrong with 1) or 2) above.

and btw, the zx12 isnt happy when its too lean on bottom actually it likes a bit richer than other motors. however this has nothing to do with your problem.

hope it helps
__________________
Serpent 720 09 mega zx 12 dsII+, Serpent 733 nova 353 tuned/sirio XXXV
Futaba, Graupner, Hudy, RB fuel
gfilos is offline   Reply With Quote
Old 08-23-2010, 05:10 AM   #4
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default

ok thanks, so you mean that problem is with gearbox not with carb? Because i didn't change gearbox settings, i left it same like for orion... Just my orion is gone (back bearing faild) so i had old zx with no head button and i put head button from orion and carb from nova based mf... And its happened... Now i put carb from orion and ill check it on track again... In hand seems to be ok... On full trottle...
__________________
facebook.com/rogergrafix
roger999 is offline   Reply With Quote
Old 08-23-2010, 06:44 AM   #5
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 6,271
Send a message via ICQ to Roelof
Default

Did you check the real head clearance with the other head button?
__________________
The quality of an answer comes with the quality of the question.
Roelof is offline   Reply With Quote
Old 08-23-2010, 07:49 AM   #6
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default

no have no old button, so i fit orion button and underhead gaskets... You mean can be wrong clerance there?
__________________
facebook.com/rogergrafix
roger999 is offline   Reply With Quote
Old 08-23-2010, 08:05 AM   #7
Tech Adept
 
gfilos's Avatar
 
Join Date: Aug 2008
Location: Greece
Posts: 230
Default

Quote:
Originally Posted by roger999 View Post
no have no old button, so i fit orion button and underhead gaskets... You mean can be wrong clerance there?
yes head clearance maybe wrong with the new button, you ll have to check it. Do your self a favor and buy a button for zx12. Its the same as picco. btw which version zx do you have? the very first one? (DSI?) if you have dsII or later, you dont really need a nova carb, it works just fine with the stock one.

But i still cant find in which way the motor could affect up-down gearing.

edit: which orion model do you have? there was a version after the first orion engine, which was made by picco, do you have this one?
__________________
Serpent 720 09 mega zx 12 dsII+, Serpent 733 nova 353 tuned/sirio XXXV
Futaba, Graupner, Hudy, RB fuel

Last edited by gfilos; 08-23-2010 at 08:11 AM. Reason: info
gfilos is offline   Reply With Quote
Old 08-23-2010, 08:23 AM   #8
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 6,271
Send a message via ICQ to Roelof
Default

Yes, take a piece of 1mm solder, bend it into a L-shape and put it into the plughole so the endtip is touching the chrome on the cilinder. Turn the flywheel arround so the solder will be squeezed between piston and button, messure the squeezed solder, with a Picco I believe the thickness must be 0.5~0.6 mm depending the size of the head. If it is far off 0.5mm you have to change it.

If it is difficult to get the solder into the plughole just remove the heatsink and screw only the button head tight with the screws using some spacers.
__________________
The quality of an answer comes with the quality of the question.
Roelof is offline   Reply With Quote
Old 08-23-2010, 09:51 AM   #9
Tech Master
 
Geezatec's Avatar
 
Join Date: Oct 2007
Posts: 1,460
Default

Check one-way clutch. O/W clutch only function on load or acceleration. Clean and lube O/W and shaft. Remove 2speed shoes, and clean them with Scotts Brite. Adjusting screws, both bottom out, the 4 turns counterclockwise for starting out. Adjust to engine tuned. Speed shoes should be adjusted equally.

Good Luck!!
Geezatec is offline   Reply With Quote
Old 08-23-2010, 09:58 AM   #10
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default

Quote:
Originally Posted by gfilos View Post
yes head clearance maybe wrong with the new button, you ll have to check it. Do your self a favor and buy a button for zx12. Its the same as picco. btw which version zx do you have? the very first one? (DSI?) if you have dsII or later, you dont really need a nova carb, it works just fine with the stock one.

But i still cant find in which way the motor could affect up-down gearing.

edit: which orion model do you have? there was a version after the first orion engine, which was made by picco, do you have this one?
so i have zx ds II but dont have carb from that engine. i put carb from orion... orion is i hope from picco... i think i will buy that button for zx is not expensive but i hope is only one size it?
__________________
facebook.com/rogergrafix
roger999 is offline   Reply With Quote
Old 08-23-2010, 10:03 AM   #11
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default

Quote:
Originally Posted by Roelof View Post
Yes, take a piece of 1mm solder, bend it into a L-shape and put it into the plughole so the endtip is touching the chrome on the cilinder. Turn the flywheel arround so the solder will be squeezed between piston and button, messure the squeezed solder, with a Picco I believe the thickness must be 0.5~0.6 mm depending the size of the head. If it is far off 0.5mm you have to change it.

If it is difficult to get the solder into the plughole just remove the heatsink and screw only the button head tight with the screws using some spacers.
if i good understand... space between piston and button should be 0.5-0.6 mm? Is that right? i Hope ill find 1mm solder... if not can i cut it somehow? i just checked and i have 1.5 mm solder.... use it?
__________________
facebook.com/rogergrafix

Last edited by roger999; 08-23-2010 at 10:19 AM.
roger999 is offline   Reply With Quote
Old 08-23-2010, 10:39 AM   #12
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 6,271
Send a message via ICQ to Roelof
Default

Should work.....

Just squeeze it a bit with a pliers and try to get the flat spot in the line of the piston.
__________________
The quality of an answer comes with the quality of the question.
Roelof is offline   Reply With Quote
Old 08-23-2010, 10:58 AM   #13
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default

Quote:
Originally Posted by Roelof View Post
Should work.....

Just squeeze it a bit with a pliers and try to get the flat spot in the line of the piston.
ok... so is about 0.64 - 0.66.... i checked it again with bigger piece of solder and was about 0.7... so i took out one gasket and now is about 0.5-0.52... is very difficult check it right but for sure is not less than 0.5. Leave it or put one more gasket 0.1?

Ok, i have done it... just found view mega engine with parts and there is under button 2 gaskets 0.1 and 0.2 like in my zx now... i hope that button is same like in picco engines... clearance is about <0.5...
__________________
facebook.com/rogergrafix

Last edited by roger999; 08-23-2010 at 11:59 AM.
roger999 is offline   Reply With Quote
Old 08-23-2010, 12:10 PM   #14
Tech Champion
 
Roelof's Avatar
 
Join Date: Aug 2007
Location: Holland
Posts: 6,271
Send a message via ICQ to Roelof
Default

A to large clearance will give a low power engine, when fiering up and running it just cheack the coloring of the piston and buttonhead and the shape of the wire in the glowplug.
__________________
The quality of an answer comes with the quality of the question.
Roelof is offline   Reply With Quote
Old 08-23-2010, 12:23 PM   #15
Tech Fanatic
 
roger999's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2010
Posts: 841
Trader Rating: 13 (100%+)
Default

ok what color should be ?

tomorrow ill check it on track (if the weather will let me do it), i have changed gearbox like somebody said b4... i hope will be good
__________________
facebook.com/rogergrafix
roger999 is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Spec-R Gear diff review P.I.M.P Electric On-Road 890 08-31-2013 05:16 AM
jumping tips????? tweeter79 Electric Off-Road 22 08-01-2009 11:00 PM
Gearing Help/ SPUR GEAR stripping ! rc18r TomElEctric! Micro and Mini Scales 12 04-06-2009 09:25 PM
Jumping back into the ring -- Looking for the right setup Altrodesigns Electric On-Road 13 05-24-2005 05:25 PM
gear ratio 101 - gearing more important than motor? cybertoolzz Nitro On-Road 15 04-01-2003 06:49 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 09:18 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net