soundbeltfarm
5th April 2008, 19:38
Well i have bought a second hand 04 ktm 50sx pro senior for him to start racing with.
He has been on a TTR 50 for about 7 months but wanted more and he did need it.
well the clutch on the ktm was like a light switch either off or just about full power.
the centrifugal clutch started to engage at 8500 - 9000 rpm.
so the hit of power was huge when it kicked in.
He did enjoy it but he was constantly blipping the throttle and it was basiclly point and shoot to ride.
he was not confident in standing up as when it took off he found it hard to hold his weight forward so would always sit down.
he has not long turned 6 yrs.
i looked on KTMtalk and i read how some people are changing the clutch.
the standard clutch works with a series of cupped washers that flatten out at revs which engages.
on the KTM 50 mini adventure they have the same clutch but instead on the series of 14 cupped washers they use a spring.
what i found on ktmtalk was that some people were using the springs and then shim on top of the spring to add pre load and thus increase the rpm required to engage clutch.
This has been a total success as now the clutch engaes at i'd say 3-4k rpm and it has nice linear drive then power band hits but luke is already in motion and can stand while the hit of power band comes on.
this has made him feel so much more in control and he is not blipping the throttle around corners, that is the major cause of over heating.
i will prob leave his bike like this for a week maybe then add another .5mm shim to add to preload and then add one more then go back to the full on cupped washer system.
i advise anyone that has got one of these bikes and their kid is not to confident on it to give this a try.
a couple of ktm dealers were not keen on this, whne i asked why they couldn't give me an answer.
alot of people are doing this in australia as the bikes dont over heat as the clutch is not getting blipped all the time.
i will put a 10 tooth CS sprocket on tomoro to help him get drive more faster at the exspense of top end .
the standard is an 11 tooth.
also put 200 - 250ml oil instead of the 150ml .
the total cost of doing this was 21 dollars for the springs and my time which is well worth it being spent on my kids.
The ktm dealers i spoke to are keen to hear how this goes.
I just thought i'd put this write up here incase anyone is getting one of these bikes for their kids or ar ehaving trouble with overheating or kids confidence.
plus you dont have to keep measuring shim stacks.
just change oil and you're off.
He has been on a TTR 50 for about 7 months but wanted more and he did need it.
well the clutch on the ktm was like a light switch either off or just about full power.
the centrifugal clutch started to engage at 8500 - 9000 rpm.
so the hit of power was huge when it kicked in.
He did enjoy it but he was constantly blipping the throttle and it was basiclly point and shoot to ride.
he was not confident in standing up as when it took off he found it hard to hold his weight forward so would always sit down.
he has not long turned 6 yrs.
i looked on KTMtalk and i read how some people are changing the clutch.
the standard clutch works with a series of cupped washers that flatten out at revs which engages.
on the KTM 50 mini adventure they have the same clutch but instead on the series of 14 cupped washers they use a spring.
what i found on ktmtalk was that some people were using the springs and then shim on top of the spring to add pre load and thus increase the rpm required to engage clutch.
This has been a total success as now the clutch engaes at i'd say 3-4k rpm and it has nice linear drive then power band hits but luke is already in motion and can stand while the hit of power band comes on.
this has made him feel so much more in control and he is not blipping the throttle around corners, that is the major cause of over heating.
i will prob leave his bike like this for a week maybe then add another .5mm shim to add to preload and then add one more then go back to the full on cupped washer system.
i advise anyone that has got one of these bikes and their kid is not to confident on it to give this a try.
a couple of ktm dealers were not keen on this, whne i asked why they couldn't give me an answer.
alot of people are doing this in australia as the bikes dont over heat as the clutch is not getting blipped all the time.
i will put a 10 tooth CS sprocket on tomoro to help him get drive more faster at the exspense of top end .
the standard is an 11 tooth.
also put 200 - 250ml oil instead of the 150ml .
the total cost of doing this was 21 dollars for the springs and my time which is well worth it being spent on my kids.
The ktm dealers i spoke to are keen to hear how this goes.
I just thought i'd put this write up here incase anyone is getting one of these bikes for their kids or ar ehaving trouble with overheating or kids confidence.
plus you dont have to keep measuring shim stacks.
just change oil and you're off.