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2015 SGS motor mods

Still haven't put it on the dyno yet, but I have logged 500 miles already. I took it easy for the first 350 miles (kept it under 4K) and have been running it all the way to redline ever since (anytime the urge hits me). The motor is very strong (a HUGE difference over the stock setup) and I absolutely love it! Throttle response is super crisp and reacts to even the slightest twist. My wife has even enjoyed the full throttle, max rpm hits that I've made with her on the back. She kept saying "You like that don't you?" Lol. I don't know what kind of numbers it's going to put down on the roller, but they should be very good. The 30T pulley is perfect for my combination. IMO these heavy baggers should come with a 30/68 pulley and sprocket. I am 100% pleased with the way the bike runs as it sits now. I let my buddy (who has a '14 CVO Limited with a full V&H exhaust and SE tuner), ride it and all he kept saying was; his CVO couldn't touch it. He says he wants the same combo in his '07 Night Train. I hope to have numbers soon (just waiting on my buddy to squeeze me in on his dyno). Stay tuned.
 
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bulldog68 said:
Who , where you having it tuned ?
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My buddy has a dyno at his house here in Kansas City, Kansas. There shouldn't be much tuning needed (maybe a few tweaks here and there with the timing), because the Thundermax does one hell of a job. While pulling good numbers would be nice, I'm not too hung up on that. I just want to put the bike on the dyno to give the TM a chance to really learn and adjust the fuel curve from idle all the way to red line, since it's so risky to do on the highway.
 
Mandrew said:
He has a dyno at his house? Wow.


Sent from my iPhone using Tapatalk
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Yes he does. He used to build motors and tune bikes up until a couple of years ago. He's since gotten away from it, but still has the dyno. He actually wants to sell it, but I'm glad he still has it for the time being. Lol
 
**Performance update** - Yesterday I broke down and did something that I said I wouldn't do, which was run my buddy on his HD dealership built 110 SG. Now, I don't know everything that's been done to his motor because he keeps secrets, but he did tell me that he has 11:1 compression domed pistons, mild port work, T-man cams with a 600+ lift grind, V&H headers with Rinehart mufflers and a custom dyno tune with the SE tuner

Here's how it went down: We were cruising at 70 mph in 6th gear, when he went to WOT and pulled away from me by three bikes. I wasn't going to do anything at first, but my pride took over and I too, went WOT, walked him down and drove past him about 1 1/2 bike lengths before shutting it down. We did two more hits afterwards, both of which I made from 3rd gear. He later told me that he'd dropped to 2nd gear once and 3rd gear the final time. Both times, I ran 3rd out and banged 4th and 5th gear (with the throttle pinned during shifts) and pulled away effortlessly 2 1/2 -3 bike lengths (by his own admission). We shut them down and had a lengthy conversation, during which he told me that he was very impressed at the performance of my 107 motor and he wasn't expecting what had just happened, to occur. We ended the conversation with him saying that I had messed up his winning streak and he was now sitting at 5W-1L. I will probably never run the bike that hard again, but am glad I had the opportunity to finally put that issue to rest, as he had been taunting me for quite some time.
 
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Belt pulley ratio males a huge difference. When I had my Wide Glide, a buddy had the same exact bike. Difference was I was 240 and he was about 525. His bike wouldn't get out of its own way. After he had the pulleys changed, he was able to stay out ahead of me for almost 1/4 mile.
 
I agree with you RoadWarior, the pulley change is by far one of the best mods that I've done! These bikes should come from the factory with 30/68 gearing IMO. I had a 31T on the bike with the stock motor and even it was a huge improvement. My buddy in question also had a 31T installed during his build too. I tried to convince him to switch to the 30T, but he thought it would be way too much with his 110 combo. While it's true that he does have a weight disadvantage over me (he weighs 255 and I weigh 166), he does have an advantage over me in that he has higher compression, higher lift cams and more cubic inches. I could be wrong, but I'd like to think that might just about even things out between us in terms of advantages vs disadvantages.
 
I was thinking about a pulley change until my last trip. I checked my speedometer with GPS and set the cruise at 86 mph in an area where the speed limit was posted as 80 mph. The speedometer said 92 and that was as high as the cruise control would go. Nope, no way am I going to make the motor rev higher. I want to be able to run fast and comfortable when I'm on boring roads in the middle of nowhere.
 
I hear you hulkss. Maybe the pulley change isn't for everyone, but for me, coming from 175 rwhp sport bike with an additional 40 hp shot of nitrous, I am used to a bike that responds a lot differently (power wise that is), than my SGS did with the factory gearing and motor. I just needed more and now the bike fits me perfectly.
 
You all are boiling my blood on this performance stuff, I have been riding my ZX12R for many years and now on my SG and feeling the pain so thinking about doing some engine work later down the road.....now my question on this tire shredder kit from Screamin Eagle (HD) with that much HP gain is there not a requirement for belt/pulley upgrade? I am talking about street version and not drag version of Screamin' Eagle Bolt-On 110CI Stage V Tire Shredder Kit Part Number 92500038...????
 
BlkDragon,

My buddy is a certified Harley technician and owns his own shop. He installed the 31T pulley for me when I was running the stock motor. In order to retain the stock belt he had to modify the stock swingarm (weld on small tabs, so that the axle adjuster cams would still allow for tightening the belt). When I decided to go with the 30T pulley, I wanted to stick with the stock belt which is 140T, vs switching to a 139T belt because I had read about lots of belt failures. This caused me to find a solution which would not only allow me to keep the stock belt, but give me flexibility if I ever wanted to play around with other gear combinations. The solution was have the stock swingarm modified 2" over with sport bike type adjusters. The stock belts are said to be the strongest on the market and should easily handle the power that the 110 SE Tire Shredder Kit puts out. Here are a few pics of the stock arm in its unmodified and modified form.
 

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Bafflingbs said:
Awesome thread! I wish I had your guts and know how.
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Thanks for the kind words Bafflingbs. I find this type of work to be a great stress reliever for me. I started doing as much of my own work on cars and motorcycles as I could about 23 years ago, after I got taken advantage of by a motorcycle shop. I know there are many shops that are quite capable of doing a great job, but my negative experiences with shops has caused me to be very leery.
 
Finally put the bike on the Dyno today. Let me clarify, that I am running the preloaded Fuel Moto tune that was for my 107 motor, cam and head combination. I didn't make any adjustments to the tune today, but the Thundermax was set to auto tune. My goal was to be in a safe environment while running the motor hard to give the TM a chance to learn new fuel curves safely. Having said that, the numbers were as follows: 4th gear pull = 107.2 rwhp & 106.8 rwtq @ 106.9 mph; 5th gear pull = 107.8 rwhp & 105.7 rwtq @ 126.3 mph and finally, 6th gear pull = 109.6 rwhp & 91.4 rwtq at 5548 rpm, with a top speed on 150.1 mph. I have an 8 minute video of the Dyno pulls, which I will upload to YouTube later and post here.
 
Well, I tried three times to load the 8 minute video and the upload was aborted each time for some unknown reason. However, my buddy did manage to record a short 1 minute video too, which I was able to upload successfully. Unfortunately there was an issue with getting my printouts, but it's not that big of a deal. Here's the video.

https://m.youtube.com/watch?feature=youtu.be&v=zdkBM1_Q8G0
 
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Here's something very interesting. The exhaust ventilation duct hose that you see the guy holding in the video was eventually strapped over my exhaust system and the hot exhaust gases burned right through. Upon seeing this, I immediately thought of the perfect name for my bike: "The Komodo Dragon" Lol

Here are the pics of the carnage.
 

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