Page 1 of 2

Mz sx125 gear shifting issue

PostPosted: Wed Jul 06, 2016 1:33 pm
by DougieL
Hello everyone hope someone can help I have owned my sx125 for about 1year I've spent my well earned money on it replacing breather pipes,air connectors,indicator and yes uprated spray clutch,tyres,oil changes,carb cleaned and it's running near perfect but one issue I've always had is when I change up mainly between 4-5-6 gears I was getting false neutrals now and again ending in screaming revs until I manage to change gear .ive recently started holding the gear lever up until the bike drives somtimes I get a delay until the engine drives and the gear locates I was wondering if anybody else suffers this with the Mz 125's rt,sm or sx versions or do you have a suggestion cure what might be causing this problem thanx dougie

Re: Mz sx125 gear shifting issue

PostPosted: Wed Jul 06, 2016 2:37 pm
by DAVID THOMPSON
check the clutch cable out and make sure it working OK and adjusted proper
check chain sprocket is it loose at the output and chain for proper tension not too tight or loose
change the oil and do not try shifting fast also make sure the lever is proper mounted on the shift rod
page at grahams
http://grahamsmotorcycles.com/web/125_Gear_Shift.htm

items 7 am 19 do the shifting if they are worn out
they may be the problem... there are little pins on 7 if worn they can be a problem
19 can also be worn
clutch basket may need removed to see
crank nut may have reverse thread
do not remember it's been since 2004 since i been there doing any of this

Re: Mz sx125 gear shifting issue

PostPosted: Fri Jul 08, 2016 10:54 am
by DougieL
Thanx for the help but before I go drastic and start going all mechanic I have checked oil level and it looked below minimum had to add about 0.2 litre to get in between marks hope this might help also I have noticed when I engage 1 st gear without engine running with clutch fully disengaged /lever pulled fully back I'm suffering from slight clutch drag through all gears is this normal for Mz's
MORK CALLING DAVE COME IN DAVE MORK CALLING DAVE COME IN DAVE

Re: Mz sx125 gear shifting issue

PostPosted: Fri Jul 08, 2016 12:36 pm
by DougieL
Thought I'd throw a picture up just as a legend lives on

Re: Mz sx125 gear shifting issue

PostPosted: Tue Jul 12, 2016 8:08 am
by stephendacosta
It is not normal for the clutch to drag.

Re: Mz sx125 gear shifting issue

PostPosted: Tue Jul 12, 2016 11:48 am
by DougieL
Reckon clutch plates could be warped or can I adjust at the clutch inside the engine maybe sort it out ,also what oil do you lot use for best results I use mogul 15w-50 is this causing drag ,previous owner treated it terrible I think it was low mileage but I've had to alter ,clean everything takes the shine off it cause these are wicked bikes when working right

Re: Mz sx125 gear shifting issue

PostPosted: Tue Jul 12, 2016 12:13 pm
by DAVID THOMPSON
there is adjustment inside on the basket
if its off then the lever will not get a full pull

Re: Mz sx125 gear shifting issue

PostPosted: Tue Jul 12, 2016 1:37 pm
by DougieL
Thanx for response worth its wait in gold this website ,gonna take it apart and check parts of gears for wear and then adjust clutch oil and filter change due anyway fingers crossed problems are obvious will get back when done in a couple of weeks

Re: Mz sx125 gear shifting issue

PostPosted: Sat Aug 06, 2016 1:18 pm
by DougieL
Alright everybody update sunny day in Birmingham uk ideal weather to attempt strip down and check gear selectors
Stripped it all down didn't look to bad but springs on fork selector felt a bit weak compared to a spare I had so swapped over ,added new oil pressure Spring while it was opened up ,put castrol racing 10w-40 oil in,Mahle oil filter on ,adjusted clutch away I went ran a dream so the moral is Dave you was right full stop.got hold of some spares really useful sump guard and scorpion exhaust will put on in 2weeks and see how it runs will throw picture up when complete thanx again

Re: Mz sx125 gear shifting issue

PostPosted: Sun Aug 07, 2016 11:42 am
by DAVID THOMPSON
you mention change in exhaust
the 125 bikes like the factory exhausts fine
the fuel use goes up on any pipe changes i have tried

Re: Mz sx125 gear shifting issue

PostPosted: Sun Aug 07, 2016 3:16 pm
by DougieL
You are right I have read previous posts where aftermarket exhausts have reaked havoc and caused running issues the guy I got it off said he just fitted and used it I might just try it and see if any problems occur if so will rip it straight back off it is a nice carbon scorpion exhaust .i have 2 weeks holiday mid August will try it then and let you know results ,I'm not gonna re jet or anything just fit and test thanx again for your help

Re: Mz sx125 gear shifting issue

PostPosted: Mon Aug 08, 2016 4:44 pm
by DAVID THOMPSON
the 125 runs very lean and in the USA
it hates the gas with the ethanol added

http://www.pure-gas.org/

Re: Mz sx125 gear shifting issue

PostPosted: Tue Aug 09, 2016 2:20 pm
by DougieL
I think I just want to here how it sounds on YouTube loads have aftermarket exhausts just curious I suppose maybe fit try then sell

Re: Mz sx125 gear shifting issue

PostPosted: Sun Aug 14, 2016 1:02 pm
by DougieL
Went for it Saturday sun was shining again got hold of some washers an exhaust clamp and fitted scorpion back box ,adapted second stage from an original exhaust ,fired it up and it roared .Decided to have a street run on it and surprisingly
It was fine ,I noticed the exhaust was running hotter than the original and boy it was louder even with the baffler in.abit too loud for me I think totally different sound ,tone than the original it felt like I had more grunt but I think I might of been more aggressive not sure sounds like a total dirt bike now ,also fitted sump guard

Re: Mz sx125 gear shifting issue

PostPosted: Mon Aug 15, 2016 4:09 am
by stephendacosta
Don't forget to go up a size on the main jet. 105