Change sprocket with a Revloc??

Need a more technical bike for altitude trail riding.

I am thinking about buying a Revloc Dyna-ring auto clutch. I am wondering if I should also go with a 51 or 52 rear sprocket? I know the Revloc will adjust to any gear setup.... but wondered if it would be better to swap.

I came from riding a 2 stroke and am finding the new 4 stroke 450 just wants to go fast and I miss the slow control. I don't want to have to fan the clutch so much in the unpredictable terrain.

Any input is appreciated.

Thnx

Edited by cybordolphin

I've got a Rekluse in mine, and I went to a 51t rear. It works well in the tight stuff and I feel like it's just enough of a compromise to still keep the top speed. It makes first gear a lot more usable for slow technical stuff.

What is your front sprocket?

13T (stock)

I used 13-52 on my 450 and it worked well in tight & technical sections. Don't expect the auto-clutch to 'adjust' for your current gearing. All you are going to do is work the clutch too hard. The auto is great for those occasions when you end up in the wrong gear at the wrong time, but there is is still no substitute for being in the correct gear all the time.

At first I went 1 smaller in the CS but that was not the ticket for my terrain and riding style unless it's super tight goat trail action so I went 1 larger in rear and it's pretty darn good. Not goat trail low but I can carry 2nd and 3rd longer. I'm not that heavy. I adjust gearing independent on auto or "normal" clutch.

I use a 13-51 with heavy FW and Rekluse Pro, great combo up to about 50mph.

I love 13 51 on my bike. I am able to use the clutch and keep in second gear on some climbs where a shift would be a bit risky. 1st is still a little too fast for slow technical rock, but a little clutch useage and it is fine. much better than the stock 13 48 other than when I want to just haul on high speed wide trails and roads. Never cared for the rekluse all the times I rode it on other people's bikes, I prefer to manually control it.

Here's the thing with gearing down for the technical stuff: Yes, it works a little, but it costs a lot more top speed than it adds low speed usability.

Let's say for the sake of the discussion that 3000 RPM is the low practical limit at which you can dependably operate a YZ450 off road. Given that they idle at around 1700-2000, I think that's realistic. With stock gearing on an '06 at that RPM, your speed in low gear is 12.7 MPH, and your speed at 9000 in 5th is 77.5 (calculated without accounting for traction issues).

If you add 3 to the back or drop one in front (roughly the same thing), your speed at 9000 in 5th will drop to 73, while your speed in 1st at 3000 will be 12 MPH even.

When I had my '03, which was stock with a 14/48, I switched to a 15/49 to add more top end and cruising speed for the desert. I had figured that I would probably want to switch the fronts out when I went to my favorite tighter trail areas, but my experience in the desert showed me that there was really very little difference at low speed between the two setups. I did change them sometimes to better match up with the corners at certain MX tracks, but that was it.

There are really only two practical fixes for the problem of tall low speed gearing, IMO, and neither is cheap. One is to swap in a WR transmission, and the other is to install a Rekluse. The WR trans swap on the later bikes is cheaper than a Z-Start Pro, but a lot more work, obviously.

Otherwise, you'll need to learn to use the clutch like Beethoven used music. Or learn to restart the engine easily. :ride:

To address the original question, if you have or intend to have a good auto clutch, just gear the bike to be workable in all other situations besides the low speed stuff. Within reason, that's probably what should be done anyway.

GrayRacer513.... it reads that you are saying perhaps it would be ok to keep the stock sprockets (for normal riding), and use the auto clutch for the other work.

I was tending to go along with needing to resprocket to make it easier on the clutch.

Surprised to see 12.0 mph vs 12.7 mph. Your right.... it does not seem to make a lot of difference in the first gear speeds. I believe you noted doing either OR (front or rear) sprocket change. But what if you change both front and rear? Would that reduce first gear speeds more than .07?

Do you feel the clutch would be happier with an auto clutch.... or fanning the clutch often?

I don't want to start another Rekluse v Revloc debate, but IMO you would be better off with a Z start Pro.

GrayRacer513.... it reads that you are saying perhaps it would be ok to keep the stock sprockets (for normal riding), and use the auto clutch for the other work.

I was tending to go along with needing to resprocket to make it easier on the clutch.

Surprised to see 12.0 mph vs 12.7 mph. Your right.... it does not seem to make a lot of difference in the first gear speeds. I believe you noted doing either OR (front or rear) sprocket change. But what if you change both front and rear? Would that reduce first gear speeds more than .07?

Do you feel the clutch would be happier with an auto clutch.... or fanning the clutch often?

In tight, rocky, technical, trails, both your clutch and yourself will like the auto clutch. I have the Rekluse z start pro, and off road FWW and love it in those areas. :ride:

Surprised to see 12.0 mph vs 12.7 mph. Your right.... it does not seem to make a lot of difference in the first gear speeds. I believe you noted doing either OR (front or rear) sprocket change. But what if you change both front and rear? Would that reduce first gear speeds more than .07?

Do you feel the clutch would be happier with an auto clutch.... or fanning the clutch often?

Simple math. Changing both equate to an addition of 6 teeth to the rear, which would make about double the difference in both cases. In other words, you'd loose about 11 mph at 9000 in fifth, but only 1.4 mph at 3000 in 1st.

How hard the Rekluse is on the clutch plates will totally depend on how much you rely on it. My son, for example, deals with this problem by going through the tight stuff so fast that he doesn't need the clutch much at all, whereas when I started getting used to mine, I actually slowed down a little and let the clutch do its job. All in all, I think it would work out with the auto clutch lasting longer than a human modulated manual clutch because the auto will always be as locked up as it can get away with.

One thing to bear in mind with the auto-engaging rings like the Rekluse EXP (not the Core...) or the Dyna Ring is that you loose at least one clutch plate by using them.

Here's the thing with gearing down for the technical stuff: Yes, it works a little, but it costs a lot more top speed than it adds low speed usability.

Let's say for the sake of the discussion that 3000 RPM is the low practical limit at which you can dependably operate a YZ450 off road. Given that they idle at around 1700-2000, I think that's realistic. With stock gearing on an '06 at that RPM, your speed in low gear is 12.7 MPH, and your speed at 9000 in 5th is 77.5 (calculated without accounting for traction issues).

If you add 3 to the back or drop one in front (roughly the same thing), your speed at 9000 in 5th will drop to 73, while your speed in 1st at 3000 will be 12 MPH even.

When I had my '03, which was stock with a 14/48, I switched to a 15/49 to add more top end and cruising speed for the desert. I had figured that I would probably want to switch the fronts out when I went to my favorite tighter trail areas, but my experience in the desert showed me that there was really very little difference at low speed between the two setups. I did change them sometimes to better match up with the corners at certain MX tracks, but that was it.

There are really only two practical fixes for the problem of tall low speed gearing, IMO, and neither is cheap. One is to swap in a WR transmission, and the other is to install a Rekluse. The WR trans swap on the later bikes is cheaper than a Z-Start Pro, but a lot more work, obviously.

Otherwise, you'll need to learn to use the clutch like Beethoven used music. Or learn to restart the engine easily. :ride:

To address the original question, if you have or intend to have a good auto clutch, just gear the bike to be workable in all other situations besides the low speed stuff. Within reason, that's probably what should be done anyway.

Wow, I just posted essentially the same thing in another thread (but far less detailed!). I don't like to gear down, as a matter of fact I usually run stock, and sometimes even 13/48, in our tight western WA woods.

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