Time For 550 Clutch Mods

[Sasquatch]

No more procrastinating!

There doesnt seem to be a whole lot of info directly pertaining to clutch mods for us 550 owners, but after a bit of research and lots of advice from fellow members, I think I have learned enough to figure out what should work well for my machine and my style of riding!

I went ahead and placed a order through UTV Crap for a few pieces and parts, even though they could not confirm (have no experiance with) the part's compatibility for Grizzly 550's...and they also apparently no longer offer (any) discounts for members from (any) forum...

I decided to go with a set of 14g greaseless roller weights (in oppose to the stock 550's 16g weights), a set of greaseless cam plate sliders, 1mm shim, and a purple EPI spring.
Total cost with shipping: $122.88

I am also sending my outer front sheave to Coop45 to get the "MOD#3" machine work done.
Total cost with shipping (both ways): $125

Ultimately, my main goal is to substantially increase my low end torque, for my style of riding I am not too overly concerned with loosing a small amount of top end.

I will be snapping some pic's and documenting the job a bit as I go along for those of you looking for more info as you prepair to do your own 550 clutch mods.

Here are a few shots of todays progress -

Red neck jack stands (just on the right side to give me a better angle)


Seat, air box cover, right side panel and right side floor board removed


Off with the cover


Off with the cage


22mm nut removed to pull outer front sheave


Outer front sheave removed, ready for disassembly


Sheave disassembeled showing OEM roller weights


Thats it for today. Tomorrow I will get the sheave all cleaned up and shipped out to be machined. More pics to come as I progress!

[El Dee]

Wise choices IMO....Didn't UTV offer the pieces already machined too their spec..?? I've gotta head that route soon and was just gonna put Jack's set-up in mine...Just wondering about the UTV offerings and your decision to go with Coop..I also wanna increase the wet springs for that massive wheelie potential..

[Butch450]

Can't wait to hear your review of Coops work. I have been toying with the idea of sending him my UTV Inc. sheave, after a few communications with him about his 3+ mod. Might do it in March but not real comfortable with having my 450 down for a few weeks. Supposedly his work on that sheave will give me all the low I could want while still keeping the top end increase that the original machining already provided.

[srgrizzly700]

Nice mods. Good pics also.

Let us know how you like the mods.

[Sasquatch]

Originally Posted by El Dee

....Didn't UTV offer the pieces already machined too their spec..?? ...Just wondering about the UTV offerings and your decision to go with Coop...

Excellent question brutha...

UTV does offer a new outer sheave assembly already machined (to fit a Rhino 700), however after exchanging a couple emails with them "they" were unable/unwilling to confirm that the sheave would work properly with a 550. For that matter, they were unable/unwilling to even confirm if the roller weights and sliders (from a 700 Rhino as their parts listing states) would be compatible with a 550, nor could they recommend any particular combination of parts that would work for my machine. Based on my own research, I knew the parts listed for a 700 Rhino were the same for a 700 Grizzly (which were also the same for a 550 with the exception of lighter roller weights)...

On the other hand -

Coop45 has been very helpful answering all my questions and giving me insight to the differences of each "mod" he performs. He is VERY knowledgable in the aspect of modding atv clutches, and he is also willing to spend the time to help his potential customers decide what mod(s) will best suite their needs and particular riding style/environment. By the way, he is also the originator of the "#1,#2,and#3" clutch mods!

From what info I have found, 550's and 700's are escentially identical (reguarding clutch parts) with the exception that stock 550 roller weights weigh in @ 16g total compaired to 20g total for the 700... lots of info can be found for 700 clutch mods, but almost no info available for 550's. I based my decision (of what parts to order) on the plentiful info I found on the 700's combined with the limited info pertaining specifically to 550's and came to my own conclusion as to what I think will work best for me.

[Sasquatch]

Here are a couple pics of my outer front sheave all cleaned up before I ship it out to Coop45 for the "MOD#3" machine work. This is the first time I have ever had to remove the grease from a stock Yamaha clutch sheave... (and thankfully the last!)



Drive Belt side


Roller Weight side

[Butch450]

Squatchmo, check with Coop to be sure he is doing a stage 3+ not just stage 3. On the 3+ he even machines at the seal lip to get the belt to ride lower like on a 450 or 660. It sounds like from the price he is cause I think a 3 is cheaper then the $120 price of stage 3+ mod.

The guys at UTV Inc. don't know about what parts fit which quads. I had the same issue when ordering my parts but knew that all the stock part#s were the same for what I was ordering from them.

T, the difference between the UTV Inc. machined sheave is that it is machined in the roller ramps for increased or maintained top end. The face isn't machined. The low end increase is done by using shims. With Coop or Mad Mike stage 3 they machine the sheave face to get you your low but then you lose a little top end. So they then offer another mod , stage 2, that they mod your cam plate to regain your lost top end. No shims are used with Mad Mike or Coop 45's mods, I think I have the stage # descriptions right.

What Coop would do for my UTV Inc. sheave is his stage 3 and I wouldn't need to do stage 2 since my sheave is already machined for the top end performance. What this would allow me to do is to remove my shim and supposedly get even better low end torque then using the shims while still keeping the added top end I received from the UTV Inc. machining. I like my UTV Inc. setup but I am real curious how much better, if at all, this setup will be. If I didn't spend the money for the UTV Inc. sheave I would probably just send my stock sheave and a cam plate to Coop for the work. But since I did, I really want the work to be done on that sheave. But right now I don't feel like spending $120 for more clutch work that I don't have any idea or guarantee that it will be that much better than my set up now...make sense, I hope....

[Sasquatch]

This is "all new territory" for me, and I am thankful to have found such a great forum (GrizzlyRiders) filled with members eager to help educate me and answer my one-thousand-and-one questions!

In return I would like to share what I have learned with other members who may also be interested in this topic (yes, even help you "lurkers" too...lol) which reminds me, if anyone has questions or concerns, please feel free to post them up (or pm me) and I will do my best to address them or find someone more knowledgable than myself who can

[AZ08Grizz]

Butch, I installed my UTV Inc 700 sheave 2 wks ago with 18gm greaseless wts & orange secondary spring. It was machined at the outer roller ramps AND the inner ramps at the hub which allow the rollers to fall in closer to hub allowing the sheave to move closer to the fixed plate giving a lower starting ratio. I didn't install the 1mm shim at that time. I didn't notice any improvement in low end grunt without the shim so I will be installing it soon. Top end seems to be about the same as it was.

As far as Coops mod 2 - cam plate mod goes, Coop has said that it only improves top end speed in LOW range and not much improvement if any in high range unless you have some pretty good horsepower upgrades to the engine.

You can use shims with Coops and MM mods but you have to monitor/watch for rubbing issues on the cover. Also, on the cage if not going greaseless.

Sas, 700 stock wts are 20gms total with covers. I think 550 stock wts are 14gms without the cover and 16 gms with the covers.

[Sasquatch]

Originally Posted by AZ08Grizz

Sas, 700 stock wts are 20gms total with covers. I think 550 stock wts are 16gms without the cover and 18 gms with the covers so you might want to double check that!!! So you might find you are revving to high of RPMS before and after up shift with the 14 gm greaseless wts.

Yep!
You are half right and I am half wrong! lol I have altered my previous post for future viewers catching my error...

To confirm:
18g (total weight) rollers are to fit the 660's!

700's use 20g

550's use 16g

Stock 07 350, 09 550 & 01 600 has 14-gram rollers, with cover =16 grams.
Yamaha roller part# 4WV-17632-00-00

Stock 07 400 & 450 has 12-gram rollers, with cover =14 grams.
Yamaha roller part# 5GH-17632-00-00

Stock 07 660 has 16-gram rollers, with cover=18 grams.
Yamaha roller part# 5KM-17632-00-00

Stock 07 700 has 18-gram rollers, with cover=20 grams.
Yamaha roller part# 3B4-17632-00-00

SHIMS
Yamaha Part # 90201-225A4-00 washer plate, Thickness = 1.0mm
Yamaha Part # 90201-222FO-00 washer plate, Thickness = .5mm