Deciding 37 vs 35 tooth rear sprocket on 2013, 19 on Front is correct

[rbike_imp]

After considerations, to cover my rear, I’m going to get a 19 tooth front and both a 35 and 37 tooth rear sprocket. If during install, the 35 hits (chain drags on its’ slider), I'll install the 37 instead. One way or the other, one brand new rear sprocket will hang on the wall. I'll post pictures when I am done. Thanks all for your input. You've probably prevented me from getting a headache later.

[nymets1585_imp]

As far as the RPM issue boggling your mind, are you referring to what you are seeing on the tach or numbers that you have calculated? As discussed in another post that I will find later, it was discovered that the tachometer does not read correctly...I believe someone said it was off by 500 RPM. I hope this helps resolve your issue...

[rbike_imp]

As far as the RPM issue boggling your mind, are you referring to what you are seeing on the tach or numbers that you have calculated? As discussed in another post that I will find later, it was discovered that the tachometer does not read correctly...I believe someone said it was off by 500 RPM. I hope this helps resolve your issue...

I haven't heard about any tach problems - yet. What I was referring to is that the 2013 does 4000 rpm in 5th at 70mph with its' Tx gear ratios. Using the 2014 Tx ratios & sprockets 3824 is the calculated rpm in 6th at 70. However, the actual rpm is 3250 (shown on Ferret's tach). Something is missing in the calculations - possibly another gear or 2.

[pekingduck]

rbike, thanks for posting this topic. I did find it surprising that the 2014 was geared so tall to require only 3300 at 70mph, but I also remembered the roll-on torque was gone too. Something strange going on......I'll check the numbers again. Primary ratio wasn't changed.

Anyway, after doing my 19/37 conversion, swingarm slider clearance appears the same. Added a little with the 19 front, took a little with the 37 rear. Compressing the rear shocks or putting on slightly longer shocks would cause closer contact than this mod would.

Please publish 7th Gear's contact info, as he has moved.

[rbike_imp]

I contacted Honda Motorcycle Division
American Honda Motor Co., Inc.
P.O. Box 2200
Torrance, CA 90509-2200
Mail stop: 100-4C-7B
Telephone: (866) 784-1870
via phone and they tried to have me call Japan because they have no one stateside able to answer questions of this type - instead they took my info and maybe will get back - hold breath.

I am using 7th Gear's contact info on his website. It still works, but he is apparently very busy and it takes time before he is able to reply. I'm still waiting for his reply email to start production on the sprockets.

Regarding the slider, from looking at my bike and many posted pics, the contact point is closest to the front. By adding a larger front sprocket, that will only help. Decreasing the rear should not be that big a deal as it is further aft and higher than the slider.

With the larger 19T in the front, there should not be any problem. When including a 35T smaller rear sprocket, the chain will most likely just orbit around the low point - see white arrows in photos looking from the chain outside view.

Inside View from exhaust side


Outside View from chain side
* Added red line on top of slider outside edge to assist viewing.
* Added white arrows showing how the chain will be affected by 19/35 sprockets.

[rbike_imp]

As soon as I get my new sprockets installed around thanksgiving, I'll post an update and feedback as to how the bike performs.

BTW, FYI, I may have discovered another part of the missing "equation". On page 1-4 of the 2013 service manual, along with the gear ratios, .... It mentions a primary reduction ratio of 1.652 (75/46). If anyone has the 2014 Service manual, would they please post the corresponding data.

[rbike_imp]

I ordered new studs & nuts for the rear sprocket, bolt & washer for the front sprocket, and 2 new master links. Did anyone change these items when they installed their sprockets - either from a mod change to new sizes or from just normal wear & tear with a chain & sprocket change at 15-30K.

I am thinking, to be safe, I'll definitely change the front sprocket bolt & washer and only the rear nuts keeping the old studs in place. I'll keep the new rear studs in case something breaks during install. I'll also have a spare master link after I shorten the chain.

I checked with http://www.didchain.com/streetChains.html and the 530 comes in the one length (110 with a master link) and you are to cut it to size and rivet in the master link. So that is what I am going to do with my Honda OEM DID chain.

[rbike_imp]

Here are some pics (for the real techies) that shows the gearing relationships between the 5 & 6 speed transmissions on the 2013 and later 2014. Enjoy, but don't cause any pain looking too deep. It was just for curiosity.

[redbirds_imp]

I have been trying for two days to contact 7th Gear Designs by phone and email. Does anyone have additional contact info?

[rbike_imp]

I have been trying for two days to contact 7th Gear Designs by phone and email. Does anyone have additional contact info?

Redbirds, Copied down from my earlier post:
I am using 7th Gear's contact info on his website. It still works, but he is apparently very busy and it takes time before he is able to reply. I'm still waiting for his reply email to start production on the sprockets.

Update: He has my order and $ to manufacture my F & R sprockets. I do not have an update on his production or shipment yet, but I expect them soon. Send an email and phone call and wait is all you can do right now.