Growing my balls to jump into the carb

I had the shop re-jet, install my pipe (MRD 'Standard', not SSW), and 3x3 about a while back when I knew nothing about bikes.

Long story short - my 1/4 throttle is lacking to say the least. I feel like i have no power when I upshift and start at the 1/4 position for the next gear.

Since I do alot of commuting and mainly commuting, I would like to 'strengthen' my 1/4 throttle and if it means I have to compromise my 3/4 / WOT throttle then I'm happy to do that.

- Drz400sm '06

- MRD Standard pipe (not SSW)

- 3x3

- JD jetting

- 155 main

- 22.5 pilot with extended fuel screw

- Blue needle 4th position

- K&N Air filter

So...

From my understanding it's the pilot jet that controls 1/4 throttle?

When I say 1/4, I am referring to to going from closed throttle to taking off. So I would say this is 0 - 1/4 throttle?

Cliff notes:

- 1/4 throttle weak

- How do I improve 1/4 throttle

edit: enjoy the photo

photo.JPG

Edited by dh0licious

Is the red needle richer?

If so, might pay to swap them over.

Someone with JD experience will better qualified to comment.

Edited by Black_DRZ

Hows the slack in your throttle cable?

I'm no pro but just did my own jetting. Pulling and putting the carb back was the hardest. I tucked the rear boot behind the frame, seemed to help. Also, pretty sure you should be using a 160main jet with that set up. I put in a 25 pilot with extended screw and it runs mint! Most say 22.5. You need to find what works for your bike. Try some different combos and keep track of what you did and how it affected your bike.

D

Edited by DRZSMDUDE

Is the red needle richer?

If so, might pay to swap them over.

Someone with JD experience will better qualified to comment.

i think red needle is leaner? don't quote me though :wacko:

I had the shop re-jet, install my pipe (MRD 'Standard', not SSW), and 3x3 about a while back when I knew nothing about bikes.

Long story short - my 1/4 throttle is lacking to say the least. I feel like i have no power when I upshift and start at the 1/4 position for the next gear.

Since I do alot of commuting and mainly commuting, I would like to 'strengthen' my 1/4 throttle and if it means I have to compromise my 3/4 / WOT throttle then I'm happy to do that.

- Drz400sm '06

- MRD Standard pipe (not SSW)

- 3x3

- JD jetting

- 155 main

- 22.5 pilot with extended fuel screw

- Blue needle 4th position

- K&N Air filter

So...

From my understanding it's the pilot jet that controls 1/4 throttle?

When I say 1/4, I am referring to to going from closed throttle to taking off. So I would say this is 0 - 1/4 throttle?

Cliff notes:

- 1/4 throttle weak

- How do I improve 1/4 throttle

edit: enjoy the photo

photo.JPG

Run it under the same conditions with the airbox door removed .....Better , worse or the same..??

I think the cause of your 'problem' is the CV carb

It has got terrible throttle response, which is especially felt at those intial throttle openings, because it is a CV carb, and there is a delay between opening the throttle and the carb responding as it has to wait for the inlet tract vacuum to pull the slide up

The FCR carb is a 'pumper' and the throttle slide is directly connected to the twist grip

When you open the throttle with an FCR, it pumps gas in to prevent bogging, where as the CV carb overcomes this issue by only opening the slide as fast as the negine demands (via the pull of the vacuum)

Invest your money in a FCR - you won't believe the difference it will make

Invest your money in a FCR - you won't believe the difference it will make

I agree...maybe change the name of this thread to "Growing My Balls to Toss the carb"

I agree...maybe change the name of this thread to "Growing My Balls to Toss the carb"

the logic behind "replace x with y" means no would have ever done the 3x3 mod.

or changed pipes.

or changed tires.

instead they would just buy a new bike.

Your description sounds like my bike when I hadn't gotten the 3x3+rejet right. (Except in that case the top-end was a little flat so not *exactly* the same ... but similar.) I'm happy with the bike as it is now ...

Working on the carb is easy. It's simply a process that's a bit clumsy the first time, and you have to use a liiiiiiiittle muscle and some patience - but it's only a combination of elementary stuff.

Edited by Anthon Berg

the logic behind "replace x with y" means no would have ever done the 3x3 mod.

or changed pipes.

or changed tires.

instead they would just buy a new bike.

The logic of replacing "x with y"..?? ...Ok ..an X is always going to be an X, no matter what you do with it...

The 3x3 should be a constant with whatever carb is used..

Bikes, Fuel delivery, tyres and pipes change with technology so one should keep an open mind.....

;)

Edited by Craigo 485sm

Hows the slack in your throttle cable?

Plenty of slack! Thanks, i've always made sure I have enough.

I'm no pro but just did my own jetting. Pulling and putting the carb back was the hardest. I tucked the rear boot behind the frame, seemed to help. Also, pretty sure you should be using a 160main jet with that set up. I put in a 25 pilot with extended screw and it runs mint! Most say 22.5. You need to find what works for your bike. Try some different combos and keep track of what you did and how it affected your bike.

D

Since its not the MRD/SSW, I was advised to go with the 155 (I have MRD Standard, not SSW)

Will give t he 25 a go with my extended fuel screw.

Run it under the same conditions with the airbox door removed .....Better , worse or the same..??

Will give this a go too.

Your description sounds like my bike when I hadn't gotten the 3x3+rejet right. (Except in that case the top-end was a little flat so not *exactly* the same ... but similar.) I'm happy with the bike as it is now ...

Working on the carb is easy. It's simply a process that's a bit clumsy the first time, and you have to use a liiiiiiiittle muscle and some patience - but it's only a combination of elementary stuff.

My top end is flat too! Infact my top speed in 5th gear is about 105km/h :( How did you fix this? Since top speed is 3/4-4/4 throttle, was this the main jet that affected you?

My top end is flat too! Infact my top speed in 5th gear is about 105km/h :( How did you fix this? Since top speed is 3/4-4/4 throttle, was this the main jet that affected you?

Ha! Something's not right. Mine's still pulling at 130 km/h indicated. Mine was just felt a little flattish so I raised the needle a clip (so in the end jetting exactly as per suggestions here rather than the JD kit's manual).

I've got an oldish CRD exhaust - I doubt it flows better than a standard MRD - and I've got a 160 main jet. I'd try it ... (but I'm not an expert!)

Ha! Something's not right. Mine's still pulling at 130 km/h indicated. Mine was just felt a little flattish so I raised the needle a clip (so in the end jetting exactly as per suggestions here rather than the JD kit's manual).

I've got an oldish CRD exhaust - I doubt it flows better than a standard MRD - and I've got a 160 main jet. I'd try it ... (but I'm not an expert!)

Ok when you say you raised the needle a clip - you went to the 4th position from the 3rd position originally?

Run it under the same conditions with the airbox door removed .....Better , worse or the same..??

Craig I went ahead and did this last night. Let me explain:

- Bike is definetly louder under throttle with airbox removed. When I throttle on, I feel a different sound to the bike, and I feel like it is working a bit harder around the 1/2 throttle range. The sound around 1/2 throttle reminds me of my mates husky sm510. Not as high-tinged as my MRD Standard normally, a bit more lower tone/burble when pushing around 1/2 throttle.

- Acceleration feels slightly quicker but i'm not sure if this is placebo. it wasn't noticeable enough for me to distinguish for sure.

I also tried to play with the extended fuel screw while it was warmed up. How do you guys do this without burning yourself?! Even with the extended, I found it hard to get my hands in there. I took some white-out along and put a small dot on the screw so I would be able to count how many turns. It came straight off as I didn't realise the screw was covered in lube from when I must have lubed my throttle & clutch cables! Do you wear gloves?

Edited by dh0licious

.

Edited by dh0licious

Plenty of slack! Thanks, i've always made sure I have enough.

You don't want a lot of slack, my throttle has only about 1/8" of play before the cable pulls on the throttle wheel.

Craig I went ahead and did this last night. Let me explain:

- Bike is definetly louder under throttle with airbox removed. When I throttle on, I feel a different sound to the bike, and I feel like it is working a bit harder around the 1/2 throttle range. The sound around 1/2 throttle reminds me of my mates husky sm510. Not as high-tinged as my MRD Standard normally, a bit more lower tone/burble when pushing around 1/2 throttle.

- Acceleration feels slightly quicker but i'm not sure if this is placebo. it wasn't noticeable enough for me to distinguish for sure.

I also tried to play with the extended fuel screw while it was warmed up. How do you guys do this without burning yourself?! Even with the extended, I found it hard to get my hands in there. I took some white-out along and put a small dot on the screw so I would be able to count how many turns. It came straight off as I didn't realise the screw was covered in lube from when I must have lubed my throttle & clutch cables! Do you wear gloves?

^ bump Craig what do you think with these results?

^ bump Craig what do you think with these results?

If it's better in the lower to mid throttle settings with the door removed you could try clip 3...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now