I've had my bike for several months now, and have been planning on extensive changes to it once winter comes and cold weather forces me to stop riding daily. Since this is my first bike, and I'm new to riding, the whole process has been a learning curve. I'm not inexperienced in auto mechanics, so motorcycle mechanics don't scare me, they're simpler.
As I got more comfortable on the bike, and began riding faster, and further, I began to notice a problem with the clutch. Two things, in fact. The first was when shifting up from 1st gear to 2nd, I often get stuck in neutral. At first, I assumed it was just my inexperience as a rider, but then I began noticing that it only happened after I'd been riding for awhile and the bike was warm, it never happened when the bike was cold.
The second and more obvious issue was that when accelerating hard on the highway and shifting up through the gear, sometimes 4th gear would slip for a second. I've driven stick shift cars for decades, I know what a slipping clutch is, but my bike only has 28,000 miles on it, so that seems pretty early to have a worn out clutch.
Some research helped me discover that this is a common problem with my particular bike, the Honda Shadow VLX600. It seems the OEM clutch springs are a bit weak for this bike, and a simple swap is all that was needed. So I had the first reason to open up the guts of the bike.
Another popular modification to this bike is to advance the ignition timing a few degrees. Since that's inside the same housing, I figured I'd do both at the same time. I found a really good tutorial here. Its a bit old, and the photos were small, and my bike is newer so there was a minor difference, so I decided to take pics and write it all up. I followed the tutorial exactly and it was easy.
So here we go:
Getting In
Step 1: Drain the oil.
Follow the basic procedure for an oil change. Drain the oil, replace the drain plug, but do not add oil back to the engine.
Step 2: Remove the exhaust
My bike has after market pipes, so I only had to remove the lower one. It would be very difficult, if not impossible to remover the engine cover with the exhaust in place. The only difficult part was reaching the lower nut where the pipe meets the cylinder. Its a 12mm nut, behind and slightly to the right of the pipe. The easiest way I found to access it was with a box wrench slid between the frame and the radiator to the right of the pipe. It was still a pain, but I managed.
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| The engine cover. The exhaust has been removed and the foot peg mounting plate has been rotated down out of the way. |
I found that removing the upper mounting bolt on the foot peg plate, and rotating the plate out of the way helped when pulling the pipe out.
Step 3: Remover the engine cover.
There are fourteen 8mm bolts, one of which also anchors the clutch cable. Start by unhooking the cable. The easiest way to do this is to rotate the level forward (I used a pair of pliers to grip it) to release tension, and the end of the cable will easily pop out.
I placed a pan under the engine to catch any extra oil that might still be in the bike. Nothing came out, but I wasn't interested in an oil stain on my driveway.
Then remove all the bolts. Once all the bolts are out, the engine cover will stick in place because of the gasket. There are two tabs on the cover (pics below) that you can slide a screwdriver behind to pry it. Once the seal is broken it comes straight off. There are two locator pins, one on each side, that help align the cover, so it must be pulled straight out from the bike.
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| The lower right most bolt hole also has a tab what will make it easier to pop the seal and remove the cover. |
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| There is another tab to help remove the cover on the left side of the cover, below the oil fill cap. |
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| Inside the engine. The clutch is the big ring with the square plate in its center. The Timing magnet is the small plastic box in the upper right corner. |
Its worth noting that I put a few ounces of Sea Foam engine additive in the oil about a week before doing this, to help clean out any accumulated gunk. I bought the bike with 24,000 miles on it, and though I think it was well maintained, I had no way of knowing.
Clutch springs
Step 1:
The 4 springs are located behind the square plate in the middle of the clutch. Simply loosen all four bolts. Loosen each a little at a time and keep working around the circle until they all come out. You need to loosen them all together so the springs don't force the plate out unevenly and bind up some the bolts.
The bolts are longer than the springs, so don't worry about the plate popping off.
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| The springs exposed. |
Step 2: Swap the springs
Once the plate is off, simply slide out the old springs and slide on the new ones.
Put the square plate back on and tighten down the bolts a little at a time, working around the circle just like you did to remove it.
That's it. The clutch springs are done! If that's all your doing, then you're ready to put the cover back on.
Timing Mod
The ignition timing is controlled by the sprockets on that smaller wheel rotating past the magnet in that black plastic box. Its designed not to be adjustable, so to change it, we need to get a little creative.
My bike has one magnet. Some models have two. If yours has two, just repeat the procedure with each magnet.
Step 1: Determine the proper location of the magnet
After modifying the mounting, you'll have to put the magnet back in. To make sure you have it the right distance from the sprockets, use a feeler gauge to determine how big a gap there should be between one sprocket and the little magnet in the center of the underside of the black plastic box.
If you need to rotate the gear, just grab the clutch firmly, and rotate it until one of the sprockets is lined up with the magnet. Then measure the gap.
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| Line up one of the sprockets with the magnet, it should look like this. Then measure the gap with feeler gauge so you can put it back with the same gap. |
Step 2: Remove the timing magnet
Remover the two bolts holding the magnet in place. Follow the wires coming out of the magnet to where they enter the engine housing. You'll see that there are two set of grommets where the wire runs through the housing wall. Carefully slide these out, and the magnet is free of the engine.
You probably don't need to unhook any wiring if you're using a handheld tool to grind the plates.
Cover the exposed engine housing with a large rag or something to keep contaminants, like metal filings, from getting in while you work.
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| The raised extrusions on the back of the mounting plates will need to be removed. (On some bikes there are just little tabs to grind off.) |
Step 3: Grind off the extrusions
This is where my bike differed from the one in the tutorial, instead of tabs, mine had extrusions around the bolt holes. Regardless, the procedure is the same, grind them off with a metal grinder. I used a Dermel.
BE SURE the engine housing is covered to keep the metal filings out!
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| After grinding off the extrusions. The black marker shows which way I want to extend the bolt holes. |
Step 4: Enlarge the bolt holes
You want to move the magnet counter clockwise from its original position. So make sure you're grinding the holes in the right direction.
This is not an exact science. I've read you can move the timing as much as 6°, but it isn't really necessary to know exactly how far you're moving it. 3° or 4° seems to be what most people assume they've moved it, and that seems to produce a improvement in performance. But no one seems to obsess about exactly how much they move it.
The mounting bolts left circular impressions on the face of the mounting plates, so I used those as my guide. I elongated the bolt holes until they reached those circles. This left me enough surface to ensure a secure mounting, and helped me keep both holes the same size.
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| Both bolt holes elongated to the rings left by the mounting bolts. |
After grinding out the holes and checking the fit of the mounting bolts, thoroughly clean the filings from the magnet. Metal filings will cling to the mounting plates, collect in the corners of the piece and on the magnet on the underside, because the whole thing is magnetized. Clean it VERY thoroughly to make sure no bits of metal end up inside your engine.
Step 5: Remount the timing magnet
Loosely install the bolts, and slide the magnet as far counter clockwise as the enlarged bolt holes will allow. Then finger tighten the bolts.
Using a feeler gauge, position the magnet the same distance from the sprocket it was originally. Then snug the bolts down.
Finally, slide the wire grommets back into their slots in the engine housing wall. Make sure they seat all the way in.
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| The modified magnet reinstalled. Notice how it no longer lines up with the sprocket, |
That's it. The timing has been changed. Time to close it all up!
Closing Up
Step 1: The gasket
Closing up is pretty much the reverse of opening up. My bike does not use a paper gasket, instead I used a silicone gasket maker designed for high temp engine components. I ran a bead all the way around the housing cover, encircling all the bolt holes. Its easier to work with the cover than the engine, but it doesn't technically matter which of the two surfaces you put the silicone on.
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| Silicone gasket maker encircling all bolt holes on the engine cover. |
Tight the bolts just until the silicone begins to ooze out. Then stop and let it set for an hour (or whatever your directions tell you).
After its set, finish tightening the bolts. DO NOT over tighten. I managed to break off one bolt. With 13 others and the gasket, I'm sure I won't have any leaks, but eventually, I'm going to have to extract it or re-tap the whole. But I'll leave that until the next time I need to get into the engine unless I notice it leaking.
Connect the clutch cable.
Step 2: Oil
Now you can finish your oil change. Fill it up like you normally would.
Since I was grinding metal near the open engine. I plan to change the oil again in a thousand miles, to help get out any filings that might have gotten past all my cleaning efforts.
Testing It All Out!
The Clutch
The first ride immediately proved the new springs an improvement. I had not really noticed anything wrong with shifting besides the issues I mentioned above, but the clean, fast engagement I feel now is a definite improvement, in all gears.
I'm not sure how much stiffer the Barnett springs I bought are over the OEMs, but the clutch is a bit stiffer to pull, but no too hard, and the slipping has stopped.
Out on the highway, accelerating into traffic, each gear just snaps into place and the bike goes. No hesitation or slipping. It feels more confident, if that's a word I can apply to an motorcycle. Definitely worth doing.
The Timing
The first thing I noticed is the sound of the engine. Its subtle, and no one who doesn't ride this particular bike every day would notice it, but its just a little different, a little quicker sounding.
Driving in my neighborhood, where I never get out of second gear, I immediately noticed it no longer sputtered when I cut the throttle to coast to a stop sign going down hill (before I pull in the clutch). The sputtering is something I'd noticed from the beginning, and assumed it had to do with the air/fuel mix, but I had not gotten around to adjusting it. Changing the timing seems to have fixed that.
Out on the road, throttle response is better. When I crack it open, it ramps up quicker. Its not a huge change, again, something only noticeable to someone very familiar with this particular bike, but its very nice.
On the highway, in traffic, where this bike lacks the power and quickness
of a sport bike, its nice to feel that when I rip the throttle, I have a little more pep in the response. This was also a mod well worth doing.
The whole process took about 2 hours (not counting waiting for the silicone to cure) and the springs only cost $15. Add in the oil, and gasket maker, and the whole thing costs about $50. Well worth it, as the bike is now more fun to ride.
