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Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
If you go from 32/66 to 32/68 the change will only be 3%, so your speedo will be 3% out. If you have a gps you can check how accurate your speedo is before and after.
Tourer
Joined: Sep 2010
Posts: 302
Likes: 6
From: Tulsa,OK
Started chatting with a neighbor buddy of mine about wanting to get little wake up bounce to my road king. So here is what he came up with.
Changing my transmission pulleys:
2011 tri-glide 30T pulley to the front &
2007 Sportster 68T pulley to the rear.
Keeping the OEM belt for the RKC 2007.
Then upping my CAMs: either-- Knight Prowler TW555 or TMan Torqster 555s. not sure yet. I'm leaning towards Knight Prowlers but he runs TMan Cams and has bee extremely happy with them.
Spoke with the lead service manager while picking up my new trans pulleys and he said this will be a big improvement.
anyone else do these types of mods. actually I've searched the forum and found great threads that helped as well.
Changing my transmission pulleys:
2011 tri-glide 30T pulley to the front &
2007 Sportster 68T pulley to the rear.
Keeping the OEM belt for the RKC 2007.
Then upping my CAMs: either-- Knight Prowler TW555 or TMan Torqster 555s. not sure yet. I'm leaning towards Knight Prowlers but he runs TMan Cams and has bee extremely happy with them.
Spoke with the lead service manager while picking up my new trans pulleys and he said this will be a big improvement.
anyone else do these types of mods. actually I've searched the forum and found great threads that helped as well.
Road Master
Joined: Sep 2011
Posts: 771
Likes: 15
From: Cartersville, Georgia
I'm running the TW555 as part of an FM107 build and installed the 30T trike sprocket. Didn't change the rear sprocket. For me, the 30T was necessary with the TW555 as it doesn't get happy until about 3000 rpm. The speedo and fuel range will be off unless you get re-programmed. Also, that front sprocket comes off tough. You definitely need the specialized tools.
Be careful with your belt swap though. This was my belt 500 miles into my engine build break-in. It was immediately replaced under warranty and I have not had the issue since ... hopefully, that was a fluke bad belt.
Your speedo will definitely be off, but there is little you can do without a tuner that will allow speedo calibration like a TTS ... my SEPST does NOT allow that. I personally just overlook the speedo error.
Road Captain
Joined: Sep 2007
Posts: 742
Likes: 4
From: Twin Cities, MN
I am also running an FM107" setup with TW777's and 30T sprocket swap putting down 115/124. The 30-T swap was actually a recommendation direct from Bobby Wood with these cams and my riding style ... 2-up in the mountains. It was definitely the right way to go ... she gets up in the torque range (100 ft-lbs at 2,600) really quick ... perfect for curvy mountain roads.
Be careful with your belt swap though. This was my belt 500 miles into my engine build break-in. It was immediately replaced under warranty and I have not had the issue since ... hopefully, that was a fluke bad belt.
Your speedo will definitely be off, but there is little you can do without a tuner that will allow speedo calibration like a TTS ... my SEPST does NOT allow that. I personally just overlook the speedo error.
Be careful with your belt swap though. This was my belt 500 miles into my engine build break-in. It was immediately replaced under warranty and I have not had the issue since ... hopefully, that was a fluke bad belt.
Your speedo will definitely be off, but there is little you can do without a tuner that will allow speedo calibration like a TTS ... my SEPST does NOT allow that. I personally just overlook the speedo error.
Nice numbers Brian!
I see you're running the Falcon belt.... is that one tooth shorter than stock?
I've read that the Gates belts (makers of H-D OEM belts?) are the way to go.
How many miles on your current belt (and build)?
Thanks!
.
FLASH TUNERS are the only ones that can, TTS, PV2, and possibly FP3, but I'm not positive on that one.
The SE products will not, although they could, but MOCO doesn't want us to have that ability.
And I would definitely want that, making these changes, as the speedo on every Harley I've ever checked is 4% off from the factory...
Tourer
Joined: Sep 2010
Posts: 302
Likes: 6
From: Tulsa,OK
Pretty sure that's a no. I don't think any of the piggyback systems allow speedo recalibration. I'm running the Rev Perf EMS so it was fairly simple. I know the TTS and related systems can be easily programmed.
Road Master
Joined: Sep 2011
Posts: 771
Likes: 15
From: Cartersville, Georgia
Yes, I too understand the Gates Polychain is the way to go. At the time, I really didn't think it would be an issue. The builder of my motor had installed the Falcon SPC drive belts on several built bikes without a single failure and, according to him, these were some seriously flogged bikes. Since my build was done and added to my "bumper to bumper" warranty, the builder replaced the belt with the same brand at no cost thinking it was just a bad belt. With only 250 miles on that first belt and it showing wear, the current belt still looks good after a couple thousand miles.
Last edited by BrianSF-GA; Feb 15, 2015 at 02:19 PM.
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