DYNO Numbers for Baggers???
Road Warrior
Joined: Aug 2010
Posts: 1,788
Likes: 5
From: Tennessee
Absolutely no way you're shifting from 4th to 5th at 120mph. Not happening today or tomorrow. In fact I highly doubt that that engine with stock gearing could even touch 120mph. Unless you've had some serious headwork to go with that cam, the parts and exhaust you have on the bike probably aren't even generating 100hp out of that 96" motor. Have you had it dynoed? Unless that engine's cranking out 110+hp, changed the ratio of the stock tranny and the build peaks over 5800rpms, then there's no way on God's green earth that you're doing 120mph in 4th 5th or 6th gear. Setting the redline at 6400 is simply irrelevant if your peak hp was below 5500rpm which it would be with that cam and exhaust. What you've described is the most basic of engine upgrades and would barely take your stock 96" from its base hp of around 68-70 hp into the low 90hp assuming it had an excellent tune on a happy dyno.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
I don't mean to p*ss on anyone's parade but a stock 2008 softail with a 96" that has a cam, exhaust, tune and stock gearing just isn't going to do 120 without a really long downhill run and a nice tailwind.
Noted.
6th Gear
Joined: Sep 2011
Posts: 11
Likes: 0
From: Fort Worth, Texas
I've got the dyno sheet scanned, but I'm not sure how to upload an image on this forum. The "insert image" icon only allows be to point to a website. I have the image on my computer.
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Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Looking forward but please don't take any unneccessary risks if you don't already have the video. Once again, that 88ci with stock heads is probably making about 65hp. I assume its a 5sp. The gearing of that bike combined with the power of the 88 with stock heads just won't develop enough hp to push that sled to 120mph.
I had an 88 (2003 fatboy) before my current bike. I had it punched to 95", headwork, SE 258 cam, roller rockers, forged pistons, tuned and upgraded exhaust. She ran great. Produced 101hp and 103ftlbs and with the 258cam was designed to run at much higher rpms than most guys like to ride at. In upstate NH I ran wide open against my buddy's Valkyrie which is a formidable 6cyl Jap cruiser. We left the throttles wide open heading south on 93. I walked away from him at 127 (gps since the stock speedo only goes to 120) before I shut it down. I figure maybe it had a mile or 2 more in the throttle. I weigh more than most guys since I'm 6'4" and about 260 so maybe the bike would have alittle more top end with a regular sized guy.
Trust me, a stock 88, with stock heads and pistons and stock exhaust is going to die long before it hits 5000rpms. No way it makes it to 120mph with stock gearing and stock sprockets. Top end is probably between 110-115. The next 5mph takes alot more hp to push the very un-aerodynamic HD past 120.
I had an 88 (2003 fatboy) before my current bike. I had it punched to 95", headwork, SE 258 cam, roller rockers, forged pistons, tuned and upgraded exhaust. She ran great. Produced 101hp and 103ftlbs and with the 258cam was designed to run at much higher rpms than most guys like to ride at. In upstate NH I ran wide open against my buddy's Valkyrie which is a formidable 6cyl Jap cruiser. We left the throttles wide open heading south on 93. I walked away from him at 127 (gps since the stock speedo only goes to 120) before I shut it down. I figure maybe it had a mile or 2 more in the throttle. I weigh more than most guys since I'm 6'4" and about 260 so maybe the bike would have alittle more top end with a regular sized guy.
Trust me, a stock 88, with stock heads and pistons and stock exhaust is going to die long before it hits 5000rpms. No way it makes it to 120mph with stock gearing and stock sprockets. Top end is probably between 110-115. The next 5mph takes alot more hp to push the very un-aerodynamic HD past 120.
Last edited by Heatwave; Oct 3, 2011 at 06:54 AM.
6th Gear
Joined: Sep 2011
Posts: 11
Likes: 0
From: Fort Worth, Texas
Yes, it was done in late July or early August. I'd have to go find my receipt because it doesn't seem to be on my dyno sheet.