Big Bore Kits-Recommendations
Road Warrior
Joined: Apr 2007
Posts: 1,354
Likes: 1
From: S.W. Florida
You can use some type of high temp paint like the factory did during the early years before powdercoating. The problem with that is over time and with repeated cleanings it will eventually do the same thing. Powdercoat if cared for properly will last for many many years.
The downside is disassembly, cleaning, prepping and shipping the parts to a reputable vendor. Upside is you will have a finish that will last for a long time. In my case, my SE heads and Revolution kit were ordered in black powdercoat with highlighted fins. The top on the engine looks like new and there was no extra cost.
The downside is disassembly, cleaning, prepping and shipping the parts to a reputable vendor. Upside is you will have a finish that will last for a long time. In my case, my SE heads and Revolution kit were ordered in black powdercoat with highlighted fins. The top on the engine looks like new and there was no extra cost.
Advanced
Joined: Aug 2008
Posts: 89
Likes: 0
From: carson city nv
Sounds good
BM1961,
All the above replies make alot of sense from that standpoint. To answer your original question, Revolution Performance offers an 85" big bore kit that is totally bolt on and is compatible with stock HD components. I work part time for a Revolution dealer and run one myself at 10.5 to 1 compression with ported SE heads and some other goodies. We have also done several Twin Cam kits up to 98". The cylinders/pistons carry a lifetime warrany through Revolution and in our experience customer service has been top notch.
Considering the downtime, cost of re-powdercoating if needed, boring cylinders, purchasing a quality set of pistons, rings and so forth I considered this kit to be quite cost effective for my needs. You still would have your original cylinders, pistons and so forth to keep or sell to help offset the costs if you chose to do so.
Bigger is sometimes better and I'm looking at doing the 3.875 kit at 100" that would require case boring for next year. The extra cubic inches would maximize the cylinder head porting and the peformance of the cam I have installed.
Check out the website at www.revperf.com and call Andrew at 866-892-2109 with any questions. Then with the facts you can make an informed decision and go the way you wish.
All the above replies make alot of sense from that standpoint. To answer your original question, Revolution Performance offers an 85" big bore kit that is totally bolt on and is compatible with stock HD components. I work part time for a Revolution dealer and run one myself at 10.5 to 1 compression with ported SE heads and some other goodies. We have also done several Twin Cam kits up to 98". The cylinders/pistons carry a lifetime warrany through Revolution and in our experience customer service has been top notch.
Considering the downtime, cost of re-powdercoating if needed, boring cylinders, purchasing a quality set of pistons, rings and so forth I considered this kit to be quite cost effective for my needs. You still would have your original cylinders, pistons and so forth to keep or sell to help offset the costs if you chose to do so.
Bigger is sometimes better and I'm looking at doing the 3.875 kit at 100" that would require case boring for next year. The extra cubic inches would maximize the cylinder head porting and the peformance of the cam I have installed.
Check out the website at www.revperf.com and call Andrew at 866-892-2109 with any questions. Then with the facts you can make an informed decision and go the way you wish.
Ultimate HDF Member
Joined: Jul 2007
Posts: 5,716
Likes: 103
From:
To answer your intial question - There is no "big bore" kit that does not require case boring for the EVO. There is an aftermarket kit that will give you 3 more cubic inches with 10.5:1 pistons, but the increase in performance will never equal the cost. There's an endless number of mods you can do and untold thousands of parts people who will more than willing to take your money so you can have "more power"
Otherwise...
They say advice is only worth what you pay but I'll offer this free of charge. The bike is 20 years old and I'm assuming near stock. (?) Maintain it and keep it that way because every penny you spend to "modify" it for performance, will devalue it -period. A bone stock bike has much better re-sale or trade-in value. And you don't need to take my word for that, ask ANY motorcycle dealer salesman, they'll tell you the same.
That's a nice bike and 88 - 91 had the best cam ever produced for factory Evo engines. 3600 RPM in high gear will never hurt the engine provided it's maintained. So do yourself a favor and first decide whether you want to talk about what it will do after all the endless time and dollars in performance mods, or would you be happier putting those thousands of dollars into the gas tank and enjoy what mortorcycles are really about....
Otherwise...
They say advice is only worth what you pay but I'll offer this free of charge. The bike is 20 years old and I'm assuming near stock. (?) Maintain it and keep it that way because every penny you spend to "modify" it for performance, will devalue it -period. A bone stock bike has much better re-sale or trade-in value. And you don't need to take my word for that, ask ANY motorcycle dealer salesman, they'll tell you the same.
That's a nice bike and 88 - 91 had the best cam ever produced for factory Evo engines. 3600 RPM in high gear will never hurt the engine provided it's maintained. So do yourself a favor and first decide whether you want to talk about what it will do after all the endless time and dollars in performance mods, or would you be happier putting those thousands of dollars into the gas tank and enjoy what mortorcycles are really about....
Road Master
Joined: Jun 2007
Posts: 842
Likes: 47
From: New Hartford CT
Take a look at the Wood 6 cam. I have one in my 89. That one upgrade along with having the heads shaved to mildly increase compression made a huge difference. I also went to a free flowing air cleaner and exhaust at the same time. You might also consider an ignition upgrade. For a relatively small price, you can get a big increase in performance with these changes without compromising reliability or maintainability.
Mine was bone stock when I bought it, and I don't regret for a second making these upgrades. It's just a better bike now.
Mine was bone stock when I bought it, and I don't regret for a second making these upgrades. It's just a better bike now.
Tourer
Joined: May 2006
Posts: 256
Likes: 7
From: Western NC
I think one of the best upgrades would be to replace that butterfly carb with a CV. Made a world of difference on my 88'. EV 27 cam worked out real good too. Now if I can just get my gas mileage up a little bit I will be very happy.
Road Captain
Joined: Jun 2008
Posts: 640
Likes: 13
From: Hickory, NC area
I did the Kuryakyn Hypercharger and a 2:1 exhaust with a quick re-jetting on my 90. It moved the power band up a bit and kept my gas mileage great. I love the way it performs now. I might do a cam this coming winter and will likely add ignition components later. But other than that, I am going to run this engine until it drops. 5 more cubic inches doesn't seem significant enough to justify the cost. If I do ever win the lottery I might put a big engine in it, but I'm not holding my breath.
Road Master
Joined: Jun 2007
Posts: 842
Likes: 47
From: New Hartford CT
That was actually the first upgrade I made to my 89, and I agree - it was the most significant change and made a world of difference. I did that a year before the other changes. I doubt that the rest of the upgrades would have been worth as much without first upgrading the carb.
Road Captain
Joined: Jun 2008
Posts: 640
Likes: 13
From: Hickory, NC area
My 90 with CV, hypercharger and 2:1 exhaust gets a solid 42mpg very reliably.
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