Poor man's G2 mod.

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Brodie

Darksider #16 - and Proud of it !
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--- Milpitas, CA --- San Jose Bay Area
Last January I bought a G2 Throttle Tamer along with a few other goodies. It took a while but this was a good weekend to install it.

I put the bike on center stand and removed the stock throttle tube from the handlebar and was getting ready to remove the heated grip. I figured before going through the effort it would be a good idea to compare the old with the new.

(I spent about half an hour looking for the dumb thing in my garage, perhaps it's time to clean up a little.
:glare: )
It turns out when I put it side by side with the Yamaha part the G2 was about 1/2 inch shorter. A quick check on the FJRForum verified that I got the G2 for the FJR1300A model, without factory heated grips. :angry2:

Someone posted they just modified their own throttle tube so I figured "Why Not?".

The following shows what's involved...

DSC00207.jpg


This is the end view of the Yamaha throttle cam. Not much of a cam, it's round - all the same diameter.

This contributes to an abrupt change when you try to input small amounts of throttle at low RPM.

IMG_0160.jpg


I used an 1/8 inch burr in my Dremel and keep it parallel while I cut the nylon flange.

DSC00220.jpg


I made a cardstock template from the G2 and used it to scribe the profile on the Yamaha flange.

Cut a little - check a lot, you can always cut some more off - it's a bit harder to add material. :rolleyes:

IMG_0158.jpg


The modified Yamaha is on the left, G2 on the right. I still had a little more shaping to do.

IMG_0163.jpg


After the cam profile is done, the cable guide slot needs to be cut deeper.

IMG_0164.jpg


Make sure the width is even all the way down to the bottom of the groove.

You want to bring this end level with the cam profile. Don't grind into the other end where the cable barrel gets inserted.

IMG_0167.jpg


Don't let my left hand throw you, the throttle is in the closed position.

IMG_0166.jpg


This shows the throttle at full open, note the cam profile. The more you twist the throttle, the quicker it opens up.

IMG_0170.jpg


Don't worry, it all fits. It may take you a few tries but keep at it.

When it's back together it should feel smooth.

If it feels stiff the cables may not be in the right spot. Open it up and try it again.
When I got it all buttoned up I decided to pull the tank and adjust the throttle backlash, it seemed a bit excessive.


:yahoo: Mission accomplished
.
:yahoo:
I took it for a test ride before calling it a night. I must say after 59k miles working on my throttle control, this sure seems like I'm cheating.

I can get used to it very quickly.
I now have a brand new G2 unit (with teflon bushings - it's the latest design) that I don't know what to do with. Perhaps someone can make me an offer. :)

Brodie

 
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I'm interested in your G2....not sure what they go for. I think it was about $60-$70.

I will look them up and PM you w/an offer.

 
Very nice job, I might do it myself.

...When I got it all buttoned up I decided to pull the tank and adjust the throttle backlash, it seemed a bit excessive.

...

Brodie
Bound to be more backlash, there's less throttle cable wound round your "new" cam :p .

 
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Brodie has mad mechanical skilz.. Me and a dremel and a throttle tube = disaster. Just sayin... :unsure:

 
Great job Brody, especially with the pictures and write up!

I'm going to start refering to you as Mcgyver....or maybe McBrodie?! :D

 
Please do NOT use the forum to distribute a "copied from G2" throttle template. This is intellectual property of a business trying to make a living.

If you create your OWN profile, that's a different story. I, myself, had modified the stock throttle tube, and was about to start offering the service to FJR owners when G2 started making an FJR part. I'm sure it's not the same profile as the G2, though.

 
Thank you for the kind words people,

I enjoy doing this kind of stuff.
:)
Slappy, message received...

Please do NOT use the forum to distribute a "copied from G2" throttle template. This is intellectual property of a business trying to make a living.
If you create your OWN profile, that's a different story. I, myself, had modified the stock throttle tube, and was about to start offering the service to FJR owners when G2 started making an FJR part. I'm sure it's not the same profile as the G2, though.
I agree wholeheartedly.

A cam profile is someone's hard earned work. They deserve getting paid for their efforts.

For me to reverse engineer it and post on the internet would be the same as stealing.




I posted to show what was involved in modifying the stock part.

If anyone desires to modify their own part they are on their own to come up with a cam profile.

Brodie

 
Brodie,

Doesn't the G2 radius get larger than stock in the wot position to make up for the smaller radius in the lower throttle position? I've thought about doing this mod but was a little worried about the results. Does the throttle have to be twisted more degrees to get to wot or is it pretty much a non-issue?

Thanks,

Ross

 
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Put me on the same before and after list.

Before: How can a little thing like that make much difference?

After: Wow! I can't believe the difference! Why did I wait so long to do it?

(I thought about rolling my own, but, with the help of someone here on the forum, found one on Ebay.)

 
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Brodie,
Doesn't the G2 radius get larger than stock in the wot position to make up for the smaller radius in the lower throttle position? I've thought about doing this mod but was a little worried about the results. Does the throttle have to be twisted more degrees to get to wot or is it pretty much a non-issue?

Thanks,

Ross

Ross

The G2 ramps back to the stock diameter, any larger and it won't fit in the housing. You will twist a little more to get to wide open throttle, maybe 3 degrees, but I think it's a non-issue. Since most of city driving is under half throttle I think you will spend most of your time on the ramp portion of the cam profile.

After 59k (s)miles I find myself thinking about throttle control again. I got used to the off/on nature of the Yamaha part.

I will say this, it makes it easier to drive smooth.
B)
Brodie

 
I think I was the first person to modify a stock nylon tube to match the G2. Used exactly the same tools as Brodie, but didn't do nearly as much work documenting and sharing.

At that time, I did it because the G2 tube was all aluminum, and those people running heated grips were having real issues with heat dissipation. Now that G2 includes a Delrin bushing inside that keeps the aluminum portion of the tube separated from bar contact, AND makes such a super-smooth throttle, I've abandoned modifying stock throttle tubes.

G2 is a very nice product and worth the $$$.

Very nice job Brodie, and kudos to you for documenting it so well. Just in case someone wants to invest their time instead of their money. It's a lot of work, but real results either way you go.

 
I think I was the first person to modify a stock nylon tube...
Come to think of it, when I did my research I believe it was your post that convinced me to tackle the Yamaha grip.

G2 is a very nice product and worth the $$$.
I agree! I'm a machinist by trade, this is one quality piece.

Thanks for the kind words Jeff.

Brodie

 
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