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4-D
05-20-2010, 04:01 PM
Hi

I have some questions about my sons 2009 DRR 50

I just got this bike for my son a little over a month ago. He is 4 .5 and was in need of a upgrade from the little Sun L 4 stroke 100 he had got when he was 2..done a few mods to it

Put on

Nerfs
Foot Brake
Twist Throtle
Capped off

First I want to start off with saying he is definantly not a Racer..But loves to ride and by the way rides his new machine and they old...he may want to race in the future..


His hands are small and the thumb throtle was giving him issues and fatigue on his old and new ..so I was recomended to put on a Twist throtle..So I started talking to him about it before we put it on and it took some getting used to but I think he has the hang of it now

Problem I am having with it is he could get quicker response for the thumb that he is with the twist.Also now the bike dont idle as well even with adjusting the idle screw and when he pins it full throtle out of the gate sometimes it wont take it has a bog down like it is getting to much fuel ???

I used the supplied cable that came with it..the big difference is that on the carb end it didnt have a 90 deg bend on it ...dont know that I like it that it well.

I m a little woried about it staying full throtle.dont know if there is more issues with the twist over the thumb

What adjustments and recommendations do I need to do to solve these issues on idle ,take up slack and throtle response and saftey ??


Now to the clutch ..It is all factory

Any adjustments or new different type of clutch for differnt riding situations to be made so in the lower rpm range to get the bike to move rather than him getting on it and ridding it like he stole it..which he likes much to do


Phew ...that was long ..I am a hunt and pecker

Please all replies appricated

Thanks :)

selbygirl
05-20-2010, 04:31 PM
my boy had the sore thumb sindrum i took the throttle and turned it back torwds his thumb so he didnt have to xtend his thumb so far and the brake handles i bent in with a box wrech and a block of wood he couldint reach them eather seeya tommy

EthansDad
05-20-2010, 07:26 PM
Glad your boy is liking the DRR 50, its a good bike for that age.

I'd personally stick with the thumb throttle. as one suggested, rotate the assembly back so that full throttle is right under the handle bars. you might need to twist the front brake lever forward to get this positioning. if more reach is needed, you can get a thumb throttle extender.

Another thing to check on the stiff throttle is the factory splitter cable, if you are still running that. I change our about every 6 mo and lube in between to keep it smooth. if they get old, they get real hard to push in.

If he's got small hands, might also look into short grab front brake levers. some post on here about what kind works, but a good idea so that little guy can grab a handful when he needs it.

on the bog/throttle response, hard to tell without seeing it. my guess is that the new cable might be the wrong length. are you running a uni air filter? take it off and look at the carb slide (motor off) when you twist the throttle. is their some lag? does the slide go way past the top of the carb body opening? either one of those is no good.

on the 09s, there was a carb option for a 21mm or a 16mm. which do you have? I'll tell you for a bone stock, the 16mm is the ticket and you won't have to jet it much. the 21mm will work, but is too big for down low power, can cause bogs, and overall needs more jetting attention to altitude/weather, etc.

on the clutching, ah welcome to the world of DRRs! a stock 50 is pretty straight forward. as for the "rode it like he stole it" part, that is how they are meant to be ridden. you've likely noticed there is some throttle movement (rpm increase) before the bike starts moving. should be around 5000-6000rpms. that is how you want it. that is called your stall speed. you can lower that to be more like a woods bike, but the little 50 does not make power down below 5000 rpms, and starting (stalling) before then will hurt performance a lot.

poor clutching can also cause a bog down low that seems a lot like a carb issue. good way to check if its carb or CVT is to put the bike on a stand and rev it. is the bog gone? its clutching. that is not 100%, but a good place to start.

the big issue with the CVTs is the rear torque spring (big one in back pulley) goes weak and lets the belt dive before the bike starts moving. its like taking off in your car in 2nd gear, it would bog too. I'd start by finding out what spring you have in there and replace it.

As a general reference for a stock 50, a good starting place for the clutch is:

3.5 rollers
780 belt
red mallosi spring

if you read around, there are TONs of combos for the cvt setup and everyone has their options. it really does vary bike to bike, even on the same model year DRR, so do some testing and some reading on here and let us know what you see. We'll get it hooking up.

nitrofish
05-20-2010, 07:37 PM
Check your fuel mixture screw, if it is way out of adjustment you may not get it to idle properly and can also affect your low end take off. Just turn your screw in till the motor begins to stumble then back it out a quarter turn at a time waiting about 8 seconds between each quarter turn. try to find the smoothest and fastest idle. You should then be able to adjust your idle screw just fine. I think you will find that your little one will work a thumb throttle better than a twist. As the earlier post said rotate the thumb throttle upward so that the "push" is a less of a stretch. These quads don't move until 4-5000 rpm stock. He will get used to the thumb throttle, just thumb wrestle him every night and toughen him up! I like the elbow out of the carb too, less chance of it sticking, IMO. Matt.

4-D
05-21-2010, 10:32 AM
Thanks to all for the detailed info

EtahansDad

Thank you for taking the time to give me all that info ..I will do the checks you all told me and recommendations when I get time and get back





A very knowledgable person on here when I told them about my situation told me to go to the twist or rather highly recommended it..said it was very good for his boy ...so I did..

I can always go back.. but the factory set up lacked ?? ...2 cables ... and so on most must be just running one cable ?? ???

I will have to explain to Dillon the situation..cause he will ask why we may go back to thumb


I hope I dindnt make a mistake going to the twist throtle ??


How many are staying with the thumb on ATV ..Is it hands down thumb over twist??

Is there any special reason as to why ??

Also surely most are not using the stock setup if it is thumb..they are going to single cable and capping of the injection and using 1 cable for simplicity and smoothness

Also now that I put on the twist I have the cable that is straight in the carb with no 90.I said I dint like it and nitrofish said you didnt like it too.

I guess that is a NO NO ??
The most of the time when it dont look right it isnt ??


Thanks again for taking the time to help out

EthansDad
05-21-2010, 03:26 PM
Hey 4-D,

I think twist VS thumb is a matter of opinion, but if you look at a large race group like the nationals, 99.99 percent have the same opinion, its thumb.

there are some good posts on here as to why. one is for "its the way its done on the big bikes, so learn now", others have said its for safety like when you go into a sharp right hander, the body positioning makes throttle control hard on a quad. Again, I think a thumb can work quite well even on small hands if set up right.

If you've capped your oil injector, I hope you are pre-mixing? sure you are, but just checking.

a fresh dual cable, well lubed throttle housing, proper housing positioning and/or thumb extender will fix the issue. Of if you are not running any stock classes (from a rules standpoint) you can go back to the thumb throttle with a single pull cable which will also make it easier to push.

-EA

travis rimmer
05-21-2010, 08:20 PM
alot of people have told me its harder to hold on to the quad in the whoops with a twist throttle i dont listen though even though i should im a dirt bike motocross rider so i love the twister and i always prayed my son would turn over the 4 wheel refergerator for two wheels but he loves quads and thats what its about in my attempts to teach him dirt bikes i swapped his quad to a twister now he loves it and wont ride with out it and the guys on here are awesome very nice people makes me wish i didnt like dirtbikes so much. anyways my son diff. rides better with the twister hope this helps a little

4-D
05-22-2010, 08:28 AM
Thanks for the lost 2 posts on the twist they both have good points



I will go over the things in the above posts and try all the recommendations

But will talk to Dillon and may go back to the thumb with a single cable with a 90 on the end carb end

Logan #34's Dad
05-22-2010, 10:38 AM
Correct me if I'm wrong guys, I believe the Moose Thumb Throttle has a lesser range of motion. I have one in my trailer that I'll have to compare the two.
4-D, I bolted on an aluminum "paddle" for Logan which made it easier to push and gave him more surface to push against.

4-D
05-22-2010, 01:18 PM
Originally posted by Logan #34's Dad
Correct me if I'm wrong guys, I believe the Moose Thumb Throttle has a lesser range of motion. I have one in my trailer that I'll have to compare the two.
4-D, I bolted on an aluminum "paddle" for Logan which made it easier to push and gave him more surface to push against.


I did the samething on his 1st bike he got when he was 2..
I tried one of the extenders and didnt like it that well...and finally made him a paddle that I fixed to the thumb throtle..

When we go his new DRR 50 we tried the thumb awhile and then went to the twist

But you know all these little bikes lack on the factory throtle seems like they could be better..

I guess that is what all the aftermaket or personal ideas are for

tyler70t
05-22-2010, 03:32 PM
We cut some of the spring out from the carb, seemed to help out alot, as long as you get full throttle and it returns all the way !:cool:

dethwishwayne
09-23-2010, 05:56 PM
my daughter has really small hands xxs according to fox but she uses a twist but as soon has her hands get bigger she will go to thumb, it was just safer for her little hands cause she likes to jump and her hands kept coming off the bars.

3400ben
09-23-2010, 06:52 PM
I put a 400ex throttle house and a single pull cable on are mini. The 400ex housing is about an 1/2" shorter throw than stock. It made a big difference at the end of an hour long xc race.

fomospede
09-27-2010, 09:52 AM
theres alot of good clues here
one thing i found with the sore thumb was that he was also reaching to turn the machine so we added 1.25'' under the foot wells and sanded about an inch off of the seat, this helped him use more muscle groups to effectivley ride and control his machine
As for the high rpm stall, gear it down. this is 2 fold it will be slower but will also get him used to the sound and the effective stall ,wich if you decide to race will be what is needed to run up front
:p my .02