Mike Roen

Evolution Top End Introduction

Mike Roen
Duration:   3  mins

Description

Mike has a plan and he has put together some premium parts in order to freshen up the Evolution top end of our 1988 Heritage Softail.

This motorcycle is in pristine condition for its age. Dennis came across the motorcycle in southern California. Not only is it a one owner bike but it was meticulously maintained and stored for many years. The Heritage was delivered with only 10k miles clocked on the original speedometer.

Being that the engine has low miles, the pistons, rings, and cylinders may not need any attention at this time. However, they will be scrutinized over once Mike lifts the cylinders off of the cylinder studs. Like most Evolution motors that have not yet been rebuilt, this engine has the typical base and rocker box gasket leaks. This is a common issue. Not only does the air cooled engine have a lot of expansion, contraction, and vibration; but the original Harley Davidson gaskets were paper gaskets which are not very durable.

Mike will be reassembling this engine with metal base, head, and lower rocker box gaskets. As usual, S&S is helping us out with this rebuild. Mike will be installing a new, bolt in, S&S cam along with a new, updated, S&S (roller) cam bearing. The replacement cam will give this Evo a noticeable bump in torque without compromising start ups and dependability. The stock Harley Davidson lifters will also be replaced with S&S lifters. Although the stock valve springs will work fine with the bolt in cam and are expected to be in good working order, Mike will be upgrading the valve springs. This is for demonstration purposes for anyone who might be interested in a more aggressive Evo cam.

Mike will complete this top end by upgrading the stock Bendix carburetor to Harley’s next generation CV carburetor. Harley’s CV carburetor is a versatile and very dependable carburetor. Matched with an Arlen Ness high flow air cleaner, this Harley is going to be really responsive and a lot of fun to ride.

Make sure to watch this project Step by Step Here on FMH

Got an Evo? Watch these maintenance videos to keep it in top running condition.

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Hey, welcome back to Fix my hog. I'm Mike Rowan. We're back on the evil now. I'll bring you up to speed here if you haven't been following along. Uh This is a 1988 heritage softtail Dennis found it out in southern California. 10,000 miles one owner. It's like the perfect scenario. Uh The gas tanks were stored properly. Uh We've, we've already done the buyer's guide video on it. We did the full service and of course, if you bought an older Evo, you're gonna be faced with, uh, you know, probably a top end R and R more than likely the base gaskets are leaking. Uh If it's high mileage bike, obviously there's probably oil consumption or engine noise. Um We're gonna be updating the cam on this bike. So, really, um I'm gonna go over a couple of things here. What, you know, SNS has jumped in. Uh, we've worked with SNS for a long time. They've been in the motorcycle industry for it seems like 100 years. Obviously, we don't want to put the stock cam back in the, the stock cam is very anemic epa compliant. It basically makes the motorcycle run and that's it. And if it's a high mileage bike, the hard face could be wore on it. So we're just gonna go ahead and put a decent uh torque cam in this motorcycle. We're not too concerned about horsepower because, you know, face it. A Harley 2000 uh 4500 R PM. That's really where you live on the thing. So a build like this, we want pump gas, we want electric start, we want torque and we want the, you know, longevity. You know, we don't want to have a zipper on this motor. So nice drop in cam uh quality product. Uh Barnett, you think Barnett, you think clutches? Well, obviously they do throttle cables, they do clutch cables, they'll make custom cables for your motorcycle. We've worked with them in the past re very reputable company. We're gonna update the valve springs, you know, it does have low miles. It probably wouldn't need them. But uh we're just gonna show you the procedure on that. Uh We've, we've got a couple of nice videos on fix. My hog on that dentist will take you to a link on that lifters. Obviously, we're not gonna cut any corners. Um You know, it is a low mileage bike, your bike though. If you're in there, you're putting lifters in it cam bearing. We're gonna update the inner cam bearing go over that. And of course, these motorcycles, they came with paper gaskets and that's really was the death nail because, uh, if you think about it, that motor is expanding and tracking with heat, that paper gasket on the base gasket and on the rocker box gasket as well as paper, they deteriorate over time and, and that's what's happened on this motorcycle. We can see it sweating if we were to ride it more and more, it'd be leaking more and more. So at the, at the very least you're gonna be going and updating all the gaskets on your bike. So, ok. So also on this project, uh, we're gonna actually be updating the carburetor to a CV carburetor and, and along with that RL and kind of jumped in and they got us a, a high flow stage, one high flow air cleaner kit, which is gonna be nice because really if you're doing the C A stock air box, it's very insufficient. It's got a small inlet. You put something like an Arline S on there. It's got a cleanable air filter, it breathes all the way around on the backside of the air cleaner cover. That's what you want, you know, a little more airflow. We're probably gonna, we're gonna end up drilling the baffles out of this too. Just it's kind of a cheap way to give you a nice little tune up on the bike without spending a ton of money on, you know, buying an expensive exhaust slip on. So, uh, I think what we're gonna do first. Uh, up here is we're just gonna probably pull this upper motor mount bracket off and then we'll flip the motorcycle around and get started on the chair down.
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