Core EXP or Rekluse PRO

[Danger16]

I'm thinking of buying an 09 YZ450 for hare scrambles and enduros. I'm currently riding an 08 KTM 250 SX set up for off-road with a Rekluse PRO. I've done multiple searches on mods and opinions on the 09.

My specific question that I can't find in a search is what Rekluse should I buy, the Core EXP or the PRO. My riding is all off-road (the only time I ride a track is for practice) and I've had a Rekluse on all my bikes for the last 7 years. My #1 concern is preventing the bike from stalling. I'm looking for recommendations on which Rekluse to run. The EXP looks great but I wouldn't mind saving the money on the PRO.

So what Rekluse should I buy?

[Gunner354]

I would go with the Pro. Less money and it works flawlessly.

[grayracer513]

The main advantage of the Core EXP, as I understand it, is that it retains the original feel of the stock clutch when you use it manually. As you know from owning a Z-Start Pro, the manual override feel is, um, different. I don't think that one prevents stalling any better than the other.

[Danger16]

The main advantage of the Core EXP, as I understand it, is that it retains the original feel of the stock clutch when you use it manually. As you know from owning a Z-Start Pro, the manual override feel is, um, different. I don't think that one prevents stalling any better than the other.

I'm not overly concerned about the feel of the clutch lever, my biggest concern is stopping / eliminating stalling.

[WB450]

I would go with the Pro. Less money and it works flawlessly.

+1:thumbsup:

[Danger16]

I picked up the bike this weekend and just ordered a Rekluse PRO!

[grayracer513]

Just as a starting point, I use the inner and the short outer springs (mid RPM engagement point) and 24 balls (soft engagement rate). I found that the clutch engaged too suddenly, and would cause stalling when accelerating a gear high, etc. The "mid/soft" set up works best for me. You know about this from setting up your KTM, of course, and you may find a different setup works better for you. I know of at least two guys who run two other different setups

on otherwise nearly identical YZ450's (one runs low/hard and does a lot of manual modulation, and the other runs mid/hard).

[Gunner354]

I have always used the med/ hard as suggested by Rekluse and have never had one flame out.

Other things that you might consider are a pipe and an 06 yz cdi. Makes the motor just about perfect.

I would also use a true synthetic oil like Redline, Amsoil or Maxima ultra .

[grayracer513]

Gunner was the second example I gave. As I say, what works for you will be a matter for you to decide. Two things that lead to these kinds of variations are differences in the clutch friction plates in use, and differences in the wet clutch friction coefficients of different oils. I use Amsoil MCF, as does the other user I mentioned. Gunner uses Redline, as I recall. Either way, Rekluse recommends you set the engagement RPM as low as practicable, and use the higher engagement rate if it works for you, as these settings will increase the longevity of the clutch over "looser" setups.

[Gunner354]

Gunner was the second example I gave. As I say, what works for you will be a matter for you to decide. Two things that lead to these kinds of variations are differences in the clutch friction plates in use, and differences in the wet clutch friction coefficients of different oils. I use Amsoil MCF, as does the other user I mentioned. Gunner uses Redline, as I recall. Either way, Rekluse recommends you set the engagement RPM as low as practicable, and use the higher engagement rate if it works for you, as these settings will increase the longevity of the clutch over "looser" setups.

The clutch life has been incredible with the med/hard setting. A 20 yo b rider and he has over 400 hrs on original plates.

Actually I did try the med/soft (24 balls) once. Rekluse talked me into trying that setting. I did not like the lag feeling. Just did not give the positive hook up feel at low rpm's. This was in tight single track. May be OK in other conditions.

[Danger16]

Thanks for the advice. I'm going to plan on starting with the med/hard set-up, I would love to run a low/hard, but I don't ever use the clutch lever (and don't want to learn how again)! I hate the slipping or delayed feel of the higher/softer engagement settings, but I don't want the bike to stall.

I don't want to start an oil war, but was planning on using/trying Mobil 15w50. I've always run Rotella (dino) in the KTM 2 stroke transmissions but after reading the numerous posts on what oil to use I'm going to stay away from Rotella in the YZ. What is the cost of a full syn like Redline versus Mobil?

On another note the previous owner told me he had the valves checked and the intakes adjusted 2 hours ago at 25 hours (bought the bike with 27 hours). Should I be worried that the valves already needed an adjustment? I've heard the YZ top ends are bullet proof as long as you take care of them; however my only other experience on 4 strokes was on an '03 CRF 450 and once you made an adjustment it was only a matter of time before the top end was toast. That has been the one thing keeping from trying 4 strokes again (5+ years)! Please tell me there is a lot of life left on my '09.

My plans are to set the sag, reroute the breather hose to the airbox with mods from the sticky section, install the Rekluse, a 2.6 Clarke tank, new graphics and tires, check the jetting and change the oil. Sorry for the long post but my last question is where are people "stripping" the oil drain plug? I'm trying to figure it out from the pics and looking at my bike, but I can't piece it together (sorry if I'm being an idiot). It looks like there is a 10mm bolt on the left front and one on the right rear of the motor, both of which do not face down but parallel to the ground, as well as the oil filter on the right front of the motor with 3 x 8mm bolts. I don't want to jack up the bike on my first oil change.

Thanks from a guy excited to ride 4 strokes again (and hoping this one is reliable),

Jim

[grayracer513]

If you mean a Mobil 15w/50 other than their Mobil 1 V-Twin, I can't get into specifics because I don't have hard information on how well the other M1 oils or the rest of the Mobil line up fares when used as a gear oil. Lubing transmissions is the downfall of almost all automotive ENGINE oils, as they are simply not blended with the tougher viscosity index additives needed for use as a transmission oil, and the result is that they fall out of grade nearly instantly (2 hours or less in the case of Rotella) Many of them are remarkably good ENGINE oils, apart from that problem, but that doesn't help much during a 3 hour desert race.

The Amsoil MCF that I use costs me right around $8/qt ordered direct as a preferred customer. Don't know the price of Red-Line. If I could get Mobil 1 Racing 4T at the same price or less, I would run it, too. Unless your ambient temps where you ride are always 90 and higher, I don't think you really need a 50 weight, though.

On the drain plugs, I have no idea how people manage to strip them exactly. The exception is the "drain" bolt at 7:00 o'clock on the oil filter cover. It suffers from a bit of an engineering brain fart. I suggest you read up on the problem enough to understand why they fail:

https://www.thumpertalk.com/forum/showthread.php?t=575367

...Then apply this simple fix to prevent it. Absolutely works:

https://www.thumpertalk.com/forum/showthread.php?t=634724

[Gunner354]

Does it matter how much the oil costs if you can get hundreds of hours without a rebuild?

I like Redline and it's $13 a quart. Cheap insurance in my book. I would at minimum run a true motorcycle specific synthetic like Gray and I have suggested.

[Danger16]

I agree. So is my top end OK with an intake valve adjustment at 25 hours?

[Gunner354]

I wouldn't worry about it. We have an 09 with over 400 hours and zero adjustments.

[grayracer513]

I agree. So is my top end OK with an intake valve adjustment at 25 hours?

The key is whether the valve stays adjusted. Some settling in is fairly normal, but once that's over, it should not require another adjustment for at least that much longer, or far more. If the seats were finished right, and the coating on the valves is sound, the clearance won't change. If the seats were left too rough, cut at the wrong angle, or the hard coat has been compromised, the valve will wear too fast, and clearance will close up.

[Danger16]

The key is whether the valve stays adjusted. Some settling in is fairly normal, but once that's over, it should not require another adjustment for at least that much longer, or far more. If the seats were finished right, and the coating on the valves is sound, the clearance won't change. If the seats were left too rough, cut at the wrong angle, or the hard coat has been compromised, the valve will wear too fast, and clearance will close up.

I think the previous owner just shimmed the intake valves to adjust the clearance. Am I OK to just ride it and see how the bike runs or do I need to have someone check the valves and seats?

[grayracer513]

I agree. So is my top end OK with an intake valve adjustment at 25 hours?

Just ride it a time or two and check the clearances. If they haven't moved, it's all good. Of course, it will help if you know what they currently are, too.