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Discussion Starter #1
Well, it's been a long time in the works, but I think it's time. Been looking at a 734 kit for a while now. I've already got the Coop Mod #3 with some shims and a purple spring. I believe its at a 3.19:1 + the shims. I haven't messed with the weights yet which will probably be my first step, but I'd like to exhaust all of my clutch options before splitting the case. Not sure which setup of weights will help with my riding.

I do a ton of deep snow riding with super heavy 30" mudder inlaws on 14" ITP Tornado rims. I think they're damn near 49 lbs/tire + Rims. She can't quite get max wheel speed in low in the deep snow. I hang up around mid RPMS and I'm not really gaining or losing RPM's when I'm riding. The other 50% of my riding is dry mountain trail riding which I'll probably get 30" Blackwater Evos for non winter riding, because those alone will save me 16 lbs/a tire.

I've had heating issues since day 1 when the brush ripped my coolant hose off the motor. I've added fuel with my EHS Tuner and its helped, but for whatever reason my overflow resivor only spits the coolant out the top and it won't return to the radiator, so it's always running about 2" low in my Rad and the temp light comes on while going slow in Low. My fender well is always coated in coolant as when I ride, it's spitting coolant out of the resivor overflow regardless of how full it is.

With that in mind I realize the cooling issues with running a BBK, but I'm at the point where I need the shear power to over ride my heavy tires to get more wheel speed. I don't want to mod it out to the point of fixing it everytime I ride, so I was thinking of doing the 734 with an upgraded Rad+Fan and might skip on the cam and head work. I'm not sure how much extra power a 734 gives over a stock jug alone, but I'm ready to start saving the $ and take the plunge.

Any help with the experienced BBK runners would be appreciated, especially what all you've learned with going this route over the years. You can onky get so much research out of BBK threads before you just have to ask for updated info.

Also if anyone has any ideas as to why my coolant is being forced out my overflow's overflow would be appreciated as well. I'm not a master of weights either, so if there is any suggestions as to help with my issue that can be solved with weights and not a BBK I'm open to suggestions. Anyways keep on keep'n on and I'm going to run my grizz until the wheels fall off. I have damn near 3,000 miles of good times and 4 broken axles to prove it, so she's treated me well. I'm not the average weekend warrior with my grizz and I'm constantly running with bigger more powerful machines, and pushing the limits of our machines so it's nice when my grizz outperforms and surprises the other groups. :)
Thanks everyone for the help and support that's made this site such a success for everyone looking to mod their rides.
 
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Sounds like a really cool project.

Kinda sounds like your antifreeze issues mite be related to a bad head gasket.
 
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Vincent nailed it above about your coolant. You got a blown head gasket with a small leak bud. Leaking combustion gases into the coolant jackets. That's also why your over-heating when going slow.

About the only big thing your gonna run into with the BBK and running big, heavy tires at WFO throttle is getting the wet clutch to hold. The best way to accomplish this is with wet clutch slugs.

If you look into the Rhino forums you'll read lots of guys having issues with wet clutches lasting when making big power. The only way they cured it was with wet clutch slugs.
 

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Discussion Starter #4
Thanks for the info guys. Ya the coolant is been a pain to deal with. I don't like riding and smelling coolant the whole time lol. I'll look into wet clutch slugs. I'm sure everything needs to be serviced anyways, she get ridden pretty hard. It'll be quite the project, but then again I didn't buy it to keep it stock haha. Much appreciated guys.
 

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Discussion Starter #5 (Edited)
The other thing I was toying with was getting the Weisco 11.1 HC piston, staying with the stock bore, and starting from there. I'd probably do some head work to while it's apart and run a Spal fan on the stock Rad to see if it will keep it cool enough. I've read some good posts on the 11:1 over the BBK, so I have to do some more research to see if that would give me what I need over the 734. I'm not sure about cams, I've read that I'd lose some bottom end going with something like a stage 2 cam, and I've read some info on a raptor cam, but not sure if that will work either for my application.
 

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I'd love to watch a thread on this build. Keep us up to date!
 
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Discussion Starter #7

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The other thing I was toying with was getting the Weisco 11.1 HC piston, staying with the stock bore, and starting from there. I'd probably do some head work to while it's apart and run a Spal fan on the stock Rad to see if it will keep it cool enough. I've read some good posts on the 11:1 over the BBK, so I have to do some more research to see if that would give me what I need over the 734. I'm not sure about cams, I've read that I'd lose some bottom end going with something like a stage 2 cam, and I've read some info on a raptor cam, but not sure if that will work either for my application.
HC piston might be the answer to what you want. It definitely gives a performance increase on the Grizzly, especially on low end torque.

As for cams, the performance you get depends on what cam you choose. You can get a low-end cam, mid-cam and top-end cam.
You'll want a cam for low-end torque gains. Mudbuster Cams and Hot Cams has always had excellent cams for this application, available in several different stages for different applications or performance gains.
For your wants, I would shy away from the Raptor cam. It's peaky cam that is geared towards high end performance. You'll lose bottom end snap.
 
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Discussion Starter #9
HC piston might be the answer to what you want. It definitely gives a performance increase on the Grizzly, especially on low end torque.

As for cams, the performance you get depends on what cam you choose. You can get a low-end cam, mid-cam and top-end cam.
You'll want a cam for low-end torque gains. Mudbuster Cams and Hot Cams has always had excellent cams for this application, available in several different stages for different applications or performance gains.
For your wants, I would shy away from the Raptor cam. It's peaky cam that is geared towards high end performance. You'll lose bottom end snap.
Thanks for the info Dezz. Ya I'm beginning to lean towards the Weisco 11:1 over the 734. I figure if I need more down the road I can always go bigger. As far As the cams go I'll check those out. Low end is what I'm leaning towards yes. Those tires are obnoxiously heavy, so all of this will help. Still in the air about doing +sized valves and what not yet. If I can get away with the cam and piston I might just do that, and wet clutch slugs, might keep the purple spring or go gold, Spal fan, and I def need to get rid of that 2R Tip and get a titan exhaust lol.
 

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If I were you, I'd definitely be looking into getting a machined clutch sheave. That will help you tremendously. More than you realize. Add that to all the work your planning, and you'll have one serious Grizzly.
 

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Discussion Starter #11
If I were you, I'd definitely be looking into getting a machined clutch sheave. That will help you tremendously. More than you realize. Add that to all the work your planning, and you'll have one serious Grizzly.
I've got a Coop Mod 3 with shims. Can't remember if it's .5mm or 1.5mm and I can't see my signature with this deluxe mobile view to verify that lol, but it's there. I was at a 3.19:1 not including the shims. But there's too much rotating mass to overcome with my current setup, EHS Tuner +Lid, Coop Mod 3 + Shims, purple EPI Spring. But ya, the piston and cam will hopefully get me to a full wheel speed in low while deep snow riding. If I can reach that goal, then that's what I'm after for a bench mark. Not so worried about doing 70 in High. I'm pretty stoked to try it out. Nice excuse for replacing a head gasket if you ask me. At least that's the excuse I'll tell my wife hahaha. ;)
 
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Discussion Starter #12 (Edited)
As for cams, the performance you get depends on what cam you choose. You can get a low-end cam, mid-cam and top-end cam.
You'll want a cam for low-end torque gains. Mudbuster Cams and Hot Cams has always had excellent cams for this application, available in several different stages for different applications or performance gains.
For your wants, I would shy away from the Raptor cam. It's peaky cam that is geared towards high end performance. You'll lose bottom end snap.
So I called Hotcams, they said the 4126-M and the 4128-2 don't fit the 2014 Grizz, and that they don't make anything that does.

Wiseco said they only offer a 102mm and 103mm with a 10:1 , no 11:1 for the 2014 grizz lol.

I did call CP, they offer a complete Kit in the 11:1 102mm bore. It's their M1039A.

Guess I'll have to keep looking another good cam manufacturer that does make 2014 parts.
 

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Discussion Starter #13
Well, I got the wet clutch slugs, gold secondary spring and CP-Carrillo 11:1 Piston Kit on its way. I've been on the phone with Hotcams twice now, and have talked to a couple other mechanically savvy people about cams.

Can't seem to find anything solid on 2014-2015 grizzly cams. I asked Hotcams about possibly using a 2014 Raptor Stage 1 since none of their drop in Grizzly Cams will work. I knew it was a shot in the dark and I got a solid maybe at best lol. My buddy at the stealership is going to try and cross reference some info about that cam to see if it would physically fit, and if so, what else we'd have to do to make it work. From what I gather the Raptor Stage 1 is usually equivalent to the Hotcam Stage 2 which is kind of where I was leaning.

If there's any 2014-2015 machines out there running a cam I'd love to hear what ya got or what ya know.
 

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Webcams makes great cams.

I've heard they have better torque cams than hotcams does anyways if i was doing mine over id probably go web over my mudbuster.

as far as pistons Wiseco is proven but so is CP many run CP for years without issues. if CP can do 11:1 and wiseco cant then go that route.

make sure you get a good cometic gasket for the rebuild and dont ruin it before you clamp the head down.

If your going to a 734 you may want to upgrade your rad or make sure you definitely pull it out and clean it completely i'm saying this because you had some heat issues in the past and if it wasn't a headgasket problem which we suspect it is. then your going to need to check the rad.

Top end is alot easier to do than going deeper so id start with just what is listed first , if your changing the piston you should just do it all at once imho but thats up to you.
 
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Discussion Starter #15
Webcams makes great cams.

I've heard they have better torque cams than hotcams does anyways if i was doing mine over id probably go web over my mudbuster.

as far as pistons Wiseco is proven but so is CP many run CP for years without issues. if CP can do 11:1 and wiseco cant then go that route.

make sure you get a good cometic gasket for the rebuild and dont ruin it before you clamp the head down.

If your going to a 734 you may want to upgrade your rad or make sure you definitely pull it out and clean it completely i'm saying this because you had some heat issues in the past and if it wasn't a headgasket problem which we suspect it is. then your going to need to check the rad.

Top end is alot easier to do than going deeper so id start with just what is listed first , if your changing the piston you should just do it all at once imho but thats up to you.
Thanks for the info! I appreciate the input. I'll check them out and see what Webcams have to offer for the 2014's. And yes, I completely agree with what you're saying. I initially started wanting to do the 734, but after more research, I felt I could probably get what I was looking for power wise from the 11:1 standard bore, wet clutch slugs and a good cam. Down the road if I'm looking for more I'll do the 734 and a 3 Core Radiator and all the extras that go with that setup. Also def want to get it done all at once and get it back on the trail.
 

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Yea cams easy and webcam has good history.

Just make sure your decomp pin is correct when your done.

Piston swap also easy especially if you stick to stock mm , no boring out etc that makes things easier too make sure your cylinder still has crosshatching to break in new rings.

After that its just a mater of setting valves on the proper stroke really.

Only thing else i can really think of is be carefull with oil-lines ,do not over torque them or you will regret it i had a friend strip the top connection on my bikes head while helping me .. it wasn't cool at all and its just a weak spot essentially since aluminum threads.
 

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Discussion Starter #17
Yea cams easy and webcam has good history.

Just make sure your decomp pin is correct when your done.

Piston swap also easy especially if you stick to stock mm , no boring out etc that makes things easier too make sure your cylinder still has crosshatching to break in new rings.

After that its just a mater of setting valves on the proper stroke really.

Only thing else i can really think of is be carefull with oil-lines ,do not over torque them or you will regret it i had a friend strip the top connection on my bikes head while helping me .. it wasn't cool at all and its just a weak spot essentially since aluminum threads.
For whatever reason, both WebCam and HotCam stopped making Cams in 2013 for Grizzlies (07-13). There must be a reason no one is making drop in cams for the 2014-2015 Grizz. I Wonder why?

Ya, I also have a buddy that'll help me swap it all out. It all sounds pretty straight forward, but it'll be a first time in an ATV motor :)
 

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Discussion Starter #18
Called Web Cam today, they said the reason they probably don't have a drop in cam for the Grizzly past 2013 is because they've never had one in the shop. They're suggestion is to send my stock cam in, they'll look at it to see if they're able to hard weld and grind it down to a Raptor cam spec, and if so, it'll cost about $278 with a 2-3 week turn around time. As of right now that's my only lead on a cam so far.
 
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I believe the real reason why many aftermarket companies have little to no products for the 2014/2015 models is because it was a short lived model. It was only sold for 2 years. There just isn't even of them out there to make it worth their while of producing products for.
I could be wrong....but imo that makes the most sense.
 

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Discussion Starter #20 (Edited)
I believe the real reason why many aftermarket companies have little to no products for the 2014/2015 models is because it was a short lived model. It was only sold for 2 years. There just isn't even of them out there to make it worth their while of producing products for.
I could be wrong....but imo that makes the most sense.
It could very well be. I just can't see the difference between the previous 07- 13's motor to 14's-15's as being a deal breaker for it. I'm by no means a mechanic so I could be way off, but my buddy seems to think it could be because these are already the H.O. 700, so maybe there isn't much room for improvement to make it worth while, who knows.

I guess I didn't realize how many of the mods on here were done to the previous gens over the 14-15's in this particular area, but I haven't found anything online to show that there is some type of aftermarket support for cams in the 14-15's. Honesty it was kind of a surprise, but if I sent my Cam off to Web Cams as a Guinea Pig, and they can give it a type of raptor profile that works better over stock, maybe they'll start making something for them. I guess it's kind of hard to believe I'd be the first cam of that type in their shop, but maybe that's the case. Lol guess this build got a bit more interesting ;) Thank you for responding Dezz and Leonard. Gets old talking out loud to myself lmao. :)
 
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