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16T … Some Results. Needs further testing!

6747 Views 34 Replies 12 Participants Last post by  Shoebacca78
My friend Cameron and I, installed our 16T Jt Sprockets on Sunday and went out for a 120 mile ride.

I haven't made final any final conclusions so far, but I still don't know how much the wind affected the numbers. The last time i did tests, It was late at night and the freeway was clear. I was able to go north/south with the wind to see the boost of a tailwind!

1) With stock gearing, Intake, Yoshi, Givi A660 windshield I was regularly about to get 65+mph. And with a tailwind, I have hit the rev limiter in 4th. I didn't have the app on at the time, but that should have been 73 or 74mph.

2) With the 16T installed I was only able to get to 70mph for a very brief time. It was difficult to get there. Cameron was drafting a lot, and hit 72MPH GPS.

3) We did conduct a 3 grom race. I was surprised that our 16T started off the line faster compared to a stock Grom, but that could have been caused by any of the other mods that were on my Grom.

The reason why i want as much speed from my grom as possible, bc i do take it on the freeways a lot. I don't really care about the max speed. What I want is to be able to maintain a speed of at least 65mph into a headwind. Before I installing the chimera, there were times riding into a headwind on the freeway I slowed down to 48mph going up a very large incline! That was dangerous… When the wind is blowing that hard, just stay on the frontage road.
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Slos13, That is why i mentioned the difference from indicated vs gps.
You may need more mods, I was considering a 16t since I can wrap out +70 pretty easy on my bike
Since after the chimera install, it was performing so well, that i was hoping it had enough power to use the 16T. I'm going to keep it on there for 1-2 more tanks, to see what happens.

Hopefully soon, there will be a windless clear night so i can go have a few more test runs on the freeway.
JTF252.13, JTF252.14, JTF252.16

FYI these are generally available on amazon prime for $6-$10.

They may be out of stock. But I'm sure more in the way.

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Top right is max speed.
big letters is actual real time speed.

The Gps isn't accurate in iPhones? If i use my old garmin gps, will ya'll say that isn't an accurate gps bc it isn't using XYZ WAAS SiRF III?

Come on guys, We aren't trying to fake results here... we are simply reporting results!

But if there ain't video/ pictures it didn't happen.

So i'm going to post a few videos soon...

Once i do that, will ya'll still doubt us and say we faked the video somehow? Do i need to run a timecode at the bottom of video so that you can see we didn't edit the video?

Cameron, is a drafting nut. and has freakin brass balls! .... on the freeway i try to be 4-6 secs from the closest cage. 2 sec is good for experienced riders. i'm not one of those yet, so i need the extra distance.
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Are you sure you're on a 16t?

Theres literally no way the stock speedo will read under if you're over geared, it's math

71 speedo, 67 gps is what a 14t with a 130/70 rear tire will do
67 Is how fast he was going when he took screenshot? but it recorded a max speed of 77mph.

Cameron saw 71 on the cluster. So it is about 6 mph off.

I saw the same on my grom. At lower speeds with a 16T, it is 3mpg slower than actual speed. And at faster speeds, the speedo is 5-6mph slower than actual.
I didn't say iPhones specifically, I meant in general. My phone now has different readings than my gps. Also, on his previous pic I was using my phone to see it, not my big PC screen. I was only looking at the big number. I see the max reading now. THAT is what is supposed to be showing. An actual speed (via GPS) higher than the cluster speed since it's a larger front sprocket compared to stock. I believe others didn't notice that as well. I wasn't hating or doubting. I knew a larger front sprocket should net a higher actual speed compared to cluster speed. That's why I asked. Because a lower actual speed (the big number) didn't make sence to me since it should read backwards. Strokd saw it like I did. Honest mistake.

Get it? Higher top speed makes sense. I just saw the picture wrong. Don't take things a different way shoebacca. I was just asking a question. I didn't say I didn't believe one way or another.
ok sorry bro.... we were just posting intial results, it felt like people were accusing us of lying?

hopefully tonight i will get out at night and make some runs to see what kind of top speed i can get to.

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It's a MPH percentage difference. It's not going to be off by the same number throughout the speed range. Going 71mph dash 77mph gps equals to just under 8%. ~8% off. Try it! Go 50mph on the dash and you should read just under 54mph on the gps, which is your actual speed. Try 25mph on the dash and gps will say 27mph. Get it? Just under 2mph off @25. Just under 4mph off @50 and so on. The faster you go the more the difference will be.
oh.. no wonder why the differnece changes with speed. it is a percentage!

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sorry about piss poor video quality.

I'm using an app on my i5s. It is called isymdvr. it is a dash cam app. I have it recording what is showing on speedo. At the same time, it is recording my gps speed/ coordinates and displays my location on a map.

this wasn't a good speed run, bc of traffic, i only got a max of 67 GPS indicated.
I will use this setup again during some speed tests soon.

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