Baja Heat and Warrior Jackshaft upgrade

#1
I now have the PMR Jackshaft Plates set up to work on the Baja MB165 Mini bikes too. The standard setup will change the gear ratio from the factory
10-1 to 8.5-1 for increased top speed while still retaining a good takeoff speed. Optional ratio's also available on request.

MB165 Jackshaft Upgrade
 
#2
Can you make something that will mount a Comet or clone of a 30 series primay and secodary?
Something strong yet stll fits the MB165 frame, maybe with a 15 deg mount....
 
#3
I now have the PMR Jackshaft Plates set up to work on the Baja MB165 Mini bikes too. The standard setup will change the gear ratio from the factory
10-1 to 8.5-1 for increased top speed while still retaining a good takeoff speed. Optional ratio's also available on request.

MB165 Jackshaft Upgrade
Brad,

What would you guess-ti-mate the mph increase would be with the 10-1 to 8.5-1 ratio change with a stock 6.5 hp Warrior/Heat?

Jimmy S.
 
#4
My guess with the stock motor turning 3600 rpms you are going to get about a 4 mph increase from 20 mph to 24 mph. :eek:hmy:

BTW, sweet upgrades Promod!!!! Keep up the excellent work. I can't wait until the weather gets a little better to get modding and riding again.
 
#5
I think it would be nice if one of the forum moderators, took this post and merged it with your DB jackshaft thread, and edit the title to say both DB, MB165 jackshaft upgrade.
 
#6
This thread was intended to answerer questions I keep receiving regarding an available application for the MB165.

lonewolf57,

Bucksboysdad is right. around 5mph more top speed with this gearing and the governor intact.
Un-governed 5000rpm capable mtr should reach 40mph with this gearing depending on the mods.
Other gear ratio's available on request but going to crazy with a higher ratio may be hard on the clutch when doing allot of stop and go, hills or tight trail riding.

This is also meant to be an alternative to repair or replace the factory JS which I saw allot of problems with when I was an authorized repair center. There were numerous times when the parts were on backorder because of them failing. Mainly the chain tensioner or bearings would fail. The list price for replacement assy' from Baja used to be around 75 shipped. You can get some individual repair parts if there in stock. But I don't think the metric bearings are available separately.

Oldschool,
I am a huge fan of CVT systems. I have played with tunning them on Snow machines, Scooters, Buggies and ATV's. I feel there is nothing cooler than when you get one tunned to the max torque output of your engine and get that seamless acceleration performance.
But there is a Drag loss with tc belt systems and if there not tuned to the engines peak torque/rpm correctly they don't really work that great. My personal opinion of the comet 20-30 series tc is that it is crude compared the the roller type driver used on modern scooter cvt's like the Honda or clone GY6 Power plant. (which are very tunable and almost bulletproof). I think Comet 20-30 design system works good with a stock 6-8hp engine. But they still use up belts that were $29-39 apiece. I personally prefer direct drive. Although I do wish someone would come up with a system that was more modern, tunable and compact. That would be the bacon!
 
#7
"Un-governed 5000rpm capable mtr should reach 40mph with this gearing depending on the mods."

Would like to clarify-correct this comment based on using one of the gear ratio calculators.
With a 19in tire and 8.5-1 ratio the estimated rpm is 5200-6000rpm at 35-40mph.
Correct mods needed for 5-6000+rpm.
 
#9
imma tell yall a simple way to do this. take the bottom sprocket off: its the one on the small chain. also take the main link out of the small chain. the chain thats on the back tire sprocket combine it with the small chain and see if it fits, if it doesnt youre gonna have to take a couple of links out.now take that long chain and fit it around the clutch sprocket and that back tire sprocket and there you have it. it'll take off kinda slow but top speed wise youll be going 45-50mph like mine cuz, all youre doing is bypassing the speed governor which means disabling it. i had the same problem. if you have any problems just private message me da name is BRANDON
 

joekd

Active Member
#10
imma tell yall a simple way to do this. take the bottom sprocket off: its the one on the small chain. also take the main link out of the small chain. the chain thats on the back tire sprocket combine it with the small chain and see if it fits, if it doesnt youre gonna have to take a couple of links out.now take that long chain and fit it around the clutch sprocket and that back tire sprocket and there you have it. it'll take off kinda slow but top speed wise youll be going 45-50mph like mine cuz, all youre doing is bypassing the speed governor which means disabling it. i had the same problem. if you have any problems just private message me da name is BRANDON
Worst advice ever. I did the bypass on my baja heat 6.5 and there is no low end at all. Good luck getting up any hill without a huge headstart.

Also keep in mind how much extra load you are putting on the motor and clutch.

As mentioned I tried this, the results were so bad I put the bike back to the OEM setup again the same week.

Also this is not bypassing the governor at all, it's just changing the overall gear ratio
 
#11
imma tell yall a simple way to do this. take the bottom sprocket off: its the one on the small chain. also take the main link out of the small chain. the chain thats on the back tire sprocket combine it with the small chain and see if it fits, if it doesnt youre gonna have to take a couple of links out.now take that long chain and fit it around the clutch sprocket and that back tire sprocket and there you have it. it'll take off kinda slow but top speed wise youll be going 45-50mph like mine cuz, all youre doing is bypassing the speed governor which means disabling it. i had the same problem. if you have any problems just private message me da name is BRANDON
Where are all these people who type in broken English coming from?
Or is this a failure of our education system?
I know I spell bad but thats because I don't proof read very often although I realy should.
imma...
cuz....
yall....

Good grief.

Colour...
Tyre....
Vacuum...

See I can spell lol.
 
#12
Where are all these people who type in broken English coming from?
Or is this a failure of our education system?
I know I spell bad but thats because I don't proof read very often although I realy should.
imma...
cuz....
yall....

Good grief.

Colour...
Tyre....
Vacuum...

See I can spell lol.
hehe canadian spelling..
 
#13
Where are all these people who type in broken English coming from?
Or is this a failure of our education system?
I know I spell bad but thats because I don't proof read very often although I realy should.
imma...
cuz....
yall....

Good grief.

Colour...
Tyre....
Vacuum...

See I can spell lol.
The dude posted the same response to 3 different threads as well, I thought spammer but we'll see! That and why would you bypass the, I'll call it the jackshaft cuz datz wat it iz! Instead of re-gearing it to suit your needs? I prefer to do things the right way though, the jackshafts are part of what makes the warriors so cool IMO! And where he got the speed governer thing is probably because there are jackshaft kits sold as just that, well they call them speed reducers as they are geared that way!
 
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#14
And here is the crux of the trouble.
We want the MB165 to lay a patch and do wheelies from a dead stop and do 50 mph pinned to the bar and flat out on 21 inch monster mudders.
We can throw all the Hp and jack shaft, all the CTVs and still we are wanting for more.

If anyone disagrees speak up.....

I bolted in a set of Champion shaft mount rocker in my ported 14cc head tonight.
I finnished porting in my custom intake and tilley carb.

In the morning I will buy a new fuel tank and get my tyres.
I guess I will cave in and buy TAV ( since the elusive high low range gear box I seek simply does not exists ) and I will continue to scratch my head and throw more money and parts at this thing like we all do trying to make the bike that Baja should have in the first bloody place.
And I will break things, burn belts, not stop before the end of the trail once or twice and do a real number on my back for lack of a good Solo seat.

It's a hard road.
 
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#15
And here is the crux of the trouble.
We want the MB165 to lay a patch and do wheelies from a dead stop and do 50 mph pinned to the bar and flat out on 21 inch monster mudders.
We can throw all the Hp and jack shaft, all the CTVs and still we are wanting for more.

If anyone disagrees speak up.....

I bolted in a set of Champion shaft mount rocker in my ported 14cc head tonight.
I finnished porting in my custom intake and tilley carb.

In the morning I will buy a new fuel tank and get my tyres.
I guess I will cave in and buy TAV ( since the elusive high low range gear box I seek simply does not exists ) and I will continue to scratch my head and throw more money and parts at this thing like we all do trying to make the bike that Baja should have in the first bloody place.
And I will break things, burn belts, not stop before the end of the trail once or twice and do a real number on my back for lack of a good Solo seat.

It's a hard road.
If you have tried different sprockets on the jackshaft as well as different rear sprockets, and cannot find a happy medium I dont see where a TAV is going to help except by giving you a better variable takeoff speed! You can always convert to a true 2 speed jackshaft setup but that will require some fabwork but it is possible if you are willing to spend the $ as well! Good luck!
 
#16
Mines make it up the hill if you modify the motor to get more horsepower out of it. But now i got the bike running at 65mph and its takes off faster because of the mods i did to the engine.
 
#18
@Oldschool no what f*ck off im only 15yrs old
Look kid.
Your dealing with a lot of people who are older than you and read write and use oldspeak.

Oldspeak is the language of the ancients before the advent of texting, email and chat rooms.

I know its not easy but make a complete sentence that has one clear point, and punctuate so we can tell when the next complete thought begins.

Google things like verb, subject comma and period and hopeful we can bridge this failure to comunicate.

Second I understand you are 15.
Good for you, that's quite an achievment.
When dealing with old people like me however use of the F word face to face may result in my breaking my foot off in your bum.

You know on top of everything else.
I am wearing underware older and a dog than you that commands more respect....
I tell stories that don't go an place and people still listen to me because there is still some trueth to what I say even if its not what they asked.....
 
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#19
Mines make it up the hill if you modify the motor to get more horsepower out of it. But now i got the bike running at 65mph and its takes off faster because of the mods i did to the engine.
HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA!!!

Why do people ALWAYS LIE on the internet!!


TOTAL BULLSHIT KID!!

HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAH!!!!!!!!

If you're going to bullshit about something then at least do it somewhere people don't know what they're talking about!!


DUMBSHIT!
 
#20
65mph on $24 Chinese ATV tires... guess we won't have to worry about reading his jibberish too much longer.


And is there a "speed governor" that i haven't found yet built into one of these jackshaft sprockets? :eek:ut:
 
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