New to the forum... putting together the pieces for my motor.

[Railroad Bulls]

Hello, my name is Evan.... Michigan boy, and although I created my account a good while ago, I haven't logged on really until now, so... I am, in every sense of the word, a total newbie.

So basically, what i'd like to do is run through what I have, and see what advice or words of wisdom you folks may have. I am a worry wart... so, although i've definitely done my fair share of reading, youtube watching, etc... I just want to make sure that I have all my bases covered, because this will be my first motor build. I am a long time motorcycle rider, but I have only done basic work like carb rebuilds/rejetting on my street bikes/dirt bikes... so, i'm using this mini-bike as a jumping off point for learning more about motors and getting comfortable on doing more in depth jobs.

What I have:

My chassis is a brand new (never run), Monster Moto 80 that I bought from Walmart. Have never even put oil in the engine yet, so it is clean, and nothing is worn.

Motor is the HF 60363 Predator, which from what I understand is the hemi version.

Optional parts I have ordered and have ready to go:

ARC Billet Flywheel
ARC Billet Connecting Rod
Stage 1 performance kit from NR racing (I like to buy from Michigan folks.), which includes an under seat header, 18LB valve springs, canister style air intake with collar, and a .036 jet, along with a new head gasket.

I also wasn't sure if I needed it for the new jet, but I bought the upgraded Emulsion tube as well to make sure that extra fuel is getting to my motor.


Things i'm unclear about:

1) It seems that many people doing these builds have aftermarket cams, and although I most likely WILL mod the cam in the future, I am unclear as to how my motor will perform with the stock cam after these parts are installed.

2) As mentioned, this is going into a Monster Moto 80 frame, and I seem to be finding conflicting stories about installing this motor. In one video I watched it seemed to just drop in.... a tight fit, but went in fine none-the-less... and then in another video, with the same hemi motor, the guy said he said to cut some bolts off with a grinder to make it fit.

3) I am unclear exactly what kind of performance increase I will see with these parts.

4) Although I have found MANY guides to removing the governor, I have not recalled finding one that specifically mentioned how much faster you can go with it removed.

Lastly, if someone can point me in the right direction as to where to go from here i'd appreciate it. I am trying to go about 40mph when all is said and done. I am not looking to make this thing into a drag bike or anything. I'm just looking to have some fun and learn about engines and get my hands dirty, and hopefully smile along the way. Thanks so much guys!

OH, and if anybody knows where I can get various size sprockets/tires that will fit this thing i'd REALLY appreciate it. Especially street tires and nobbies. Thanks again!

 

[EVOL Tweety Bird]

Well if you are gong to be in the engine to install the rod and remove the governor, adding a cam is nothing. I have a Mod2 in Tweety Bird. Some love it some hate it. Pretty much have done what you want to do on the engine. I would invest in a good clutch, or if room allows a TAV can make a world of difference.

Base problem with the Hemi is it runs lean and is governed to about 3600 rpms stock.
Doing the mods, allows the engine to come alive, and builds some serious torque and horsepower. Speed is no problem with the right gearing. You will most likely find with the stock gearing you have a wheelie machine. So going to a smaller sprocket is a given. Ungoverned, you are easily going to see probably double the rpms.

Two other things. Get an NGK plug and toss the original one. Much better plug. And two, brakes. You are going to have go, you need whoa!!!

Tweety will fly, and has the torque to haul two adults up and down the hills of Road Atlanta. I know you have motorcycle experience, but minis are a whole nother thing at 40+ mph. They can be scary.

 

[Railroad Bulls]

Hey man. Thanks so much for all the info it's pretty much exactly what I was looking for! Is the Mod2 cam one that requires any modification for fitment? I.E: Having to grind down at all to make room for the rod. Or is it just a drop in and go type of part? I've seen some videos where the dude (Red Beard) is grinding down his cam, which I know was not a stock cam, to make room for the ARC Rod. I also have always used NGK plugs, but I am wondering if I should also get new wiring? I feel like it wouldn't really make much of a difference?

 

[moetrout]

I like my CS cam in my engine. It's a $50 drop in cam and has good low end torque and is rated to as much as 7000rpm. I have a Motovox mbx10 frame. I think it's close to what you have. Worst case is you drill new holes in the mounting plate. Make sure your sprocket alignment is correct. Remove the governor and with the parts you have I think you will be closer to 50mph depending on your gearing. 12/60 is a good place to start. If you want less top end and more torque you could go to 70 on the rear sprocket. Better stay over the front end when you ride it or it will have your ass on the ground. Where in Michigan are you?

 

[Railroad Bulls]

I like my CS cam in my engine. It's a $50 drop in cam and has good low end torque and is rated to as much as 7000rpm. I have a Motovox mbx10 frame. I think it's close to what you have. Worst case is you drill new holes in the mounting plate. Make sure your sprocket alignment is correct. Remove the governor and with the parts you have I think you will be closer to 50mph depending on your gearing. 12/60 is a good place to start. If you want less top end and more torque you could go to 70 on the rear sprocket. Better stay over the front end when you ride it or it will have your ass on the ground. Where in Michigan are you?

Yes from what i've read the Motovox frame is nearly the same. How do you go about making sure the sprocket alignment is correct? Thats actually something i've been curious about...

 

[Railroad Bulls]

And I am in Howell, MI. You?

 

[Railroad Bulls]

I like my CS cam in my engine. It's a $50 drop in cam and has good low end torque and is rated to as much as 7000rpm. I have a Motovox mbx10 frame. I think it's close to what you have. Worst case is you drill new holes in the mounting plate. Make sure your sprocket alignment is correct. Remove the governor and with the parts you have I think you will be closer to 50mph depending on your gearing. 12/60 is a good place to start. If you want less top end and more torque you could go to 70 on the rear sprocket. Better stay over the front end when you ride it or it will have your ass on the ground. Where in Michigan are you?

This one?

https://www.ebay.com/itm/Cm-Grind-C...:WvIAAOSwwI1ajpan:sc:USPSPriority!48843!US!-1

This one actually has a 7500 rpm rating... yowza

 

[moetrout]

I am in Milan, MI. Not too far south from you. Eric Adams (CarPlayLB on here) has stated before that he likes the CM and CS cams. Both are drop in $50 cams that perform well. As I said I like my CS cam. I drag raced my bike once last year out at Milan Dragway. My bike pulled real nice out of the hole and could hang with some of the faster bikes until it hit it's top rpm, 5500rpm at the time.

I did not mount the motor on my motovox so I have not had to align the sprockets. I have also heard of guys using laser pointers. Me, I'm old school so I would just lift the rear tire off the ground, put the chain on with the motor clamped where I think it should go and spin the rear tire to see if it's aligned. Maybe someone else has a more exact process, but I am sure my way would get you close enough.

If you run into any hard problems and want some help let me know. I like working on these things.

 

[The.MiniTard]

you should hit 40 mph with those mods easily!! You have an instagram account? We have a little db30 with similar mods and it does 40+ with me on it(220+lbs)

 

[Railroad Bulls]

you should hit 40 mph with those mods easily!! You have an instagram account? We have a little db30 with similar mods and it does 40+ with me on it(220+lbs)

I don't have an instagram account but i'm very interested in seeing any videos/pics you have

 

[Railroad Bulls]

Well like an idiot, I ordered the CM cam before I got your response, or Erics from OldMiniBikes actually. He said that I would probably be better off with the CS... so, now i'm trying to figure out how to have my order cancelled so that I can order the CS. Eric was not able to find my order on their site, but, as soon as it's cancelled i'll order the CS. Have you seen anybody with a setup similiar to mine with the CM cam? Cause if it will work just fine i'll throw it in anyways...

 

[Raskin]

Greetings..this about the best vid I've seen for predator swap on mb80. The main issues are engine will need to be stationary making use of tensioner a must and room for air filter box or pod.You could use of 1" square tube as risers on the 212 predator if needed..bad pic of mine w an intek 6.5 i had already.I didn't use the large intek gas tank... https://youtu.be/O9kj7wlNwtQ

 

[moetrout]

Well like an idiot, I ordered the CM cam before I got your response, or Erics from OldMiniBikes actually. He said that I would probably be better off with the CS... so, now i'm trying to figure out how to have my order cancelled so that I can order the CS. Eric was not able to find my order on their site, but, as soon as it's cancelled i'll order the CS. Have you seen anybody with a setup similiar to mine with the CM cam? Cause if it will work just fine i'll throw it in anyways...

I would just stick with what you ordered. The only difference I see is slightly more duration on the intake than the CS. That may be why that CM cam shows 7500 rpm and the CS is 7000 rpm. Both the CM and CS cam have .265 lift and that is where your torque is coming from.

 

[Railroad Bulls]

I would just stick with what you ordered. The only difference I see is slightly more duration on the intake than the CS. That may be why that CM cam shows 7500 rpm and the CS is 7000 rpm. Both the CM and CS cam have .265 lift and that is where your torque is coming from.

Moetrout, would it be cool with you if I PM'ed you my facebook address and/or email? It'd be nice to have someone who lives nearby be able to point me in the right direction to any tools/parts I end up needing. I'm sure this whole build will be easier than I anticipate, but... I have a brain that just looooooves to think about everything that could go wrong haha

 

[moetrout]

I sent you my contact info. I'd be happy to help if I can. I over think everything too and there's a lot to consider when trying to build a fast motor.

Tonight there is a facebook live event on OldMiniBikes.com. Eric is building a predator hemi. You should watch, good info and Eric is entertaining too. Youtube is also full of great videos. Redbeards garage did a good youtube video of building a predator hemi. When you have never done this stuff before it sure helps to see it done first, then it is a lot less intimidating.