Hobit PA50I Performance Upgrade Suggestions

David Klinikowski /

I picked up a very nice 1978 Honda hobbit PAI (450Miles) from Craig’s list. It has been sitting for 25 years but it still started. Top speed as it sits is only about 15 MPH. Obviously, it needs a carb cleaning and some general tuning up. This model is the dog of the Hobbit’s and only has a top speed of 20 MPH. Before I tear into it, I want to investigate mods I can do to improve performance and top speed. There several different performance parts and changes listed on the internet but it is not clear which ones give the biggest performance increase for the buck. Your site has lots of goodies but I may not want to spend the money on doing everything. (I’m not trying to hit 50MPH)

My goal is to improve top speed to at least 35MPH while hauling my 200lb ass around town. The following lists the various changes if found that claim improve performance. Which cost-effective ones would you suggest for achieving my goal?...OK maybe 40Mph……

• Cylinder/piston upgrade (DR70, Athena 70, etc)

• Performance Exhaust pipe(type?)

• Performance reed kit (type?)

• Carburetor or Carburetor Mod

• Larger Jet (size?)

• Notching Variator

• New variator weights

• New Ramp plate

Please comment on the above modifications and any experience you have regarding the effectiveness in improving performance. Also please suggest the parts that you would purchase if this was your ride. I am looking forward to this project and a relationship with your company. I love it out there in SF and can’t wait to visit again…..



Re: Hobit PA50I Performance Upgrade Suggestions

Before you go to far with this, you need to come up with something other than the PA50I variator ramp plate. Then if you basically turn it into a PA50II and add a Proma pipe(loud) you might be lookng at upper 30's.



Re: Hobit PA50I Performance Upgrade Suggestions

Emil Kniemel /

follow this:


where it says "How to build the buddy hobbit if you’re starting with a PA50-1"

Re: Hobit PA50I Performance Upgrade Suggestions

Yes to the above. That will get you where you want to be. Easy peasy.

Re: Hobit PA50I Performance Upgrade Suggestions

David Klinikowski /

The "buddy" article has a lot of good info. Does anyone know if the DR cylinder kits (70CC) fit onto a PA50I case?

Where can I get a new variator ramp plate for the PA50I engine?

If I enlarge the air inlet do I have to replace the reeds?

I am new to two strokes...once I get into it, it will be more obvious.

Re: Hobit PA50I Performance Upgrade Suggestions

Yes, you will just need to modify either the case or the cylinder (this is in the Wiki) due to the pesky "notch" that they put in there.

http://www.mopedarmy.com/wiki/Honda_PA_Model_Differences#Cylinder_Skirt (edited)

Re: Hobit PA50I Performance Upgrade Suggestions

DR kit is bolt on for a pa50i, aftermarket kits already have the notch grooved in.

What I would do differently.

Pii carburetor, pii intake, pii reedblock, pii ramp plate, stock shocko kit, proma pipe.

Substitue proma pipe if you want to keep your hearing, I hear its a really loud pipe! MLM maybe?

Those upgrades give you more fuel + air in.

The pii ramp plate is necessary.

I would go with the 60cc kit unless you can find a GOOD pii cylinder/piston because you cannot! Cannot! bolt on a mlm pipe or a proma, or any others to a pa50i because the header is wayyyy too small!!!

you can only bolt on pipes to a pa50ii because it has a normal sized header.

Then you upjet the pa50ii carburetor, keep the stock air filter in place, keep the rubber dick in place! dont mess with it!

Replace tires ( cheapies will do ) / tubes, grease the wheel bearings, slap some pads on if you want, lube your cables ( speedo cable, brakes, throttle, decomp ) grab some extra bulbs for if they blow. drain and replace the rear trans fluid. slap some crank seals on. To do the seals you will need a clutch puller. You can notch your variator, its not too difficult. You should window it because you can cut your leg up really well

image stolen

as far as reeds, I haven't used the boyesen yet, you could go with whatever you want. Just use the pii reedblock you need it anyway.

discussion on 60cc kit

Your going to have a few hundred more into it but itll run all the time.

anyway... you'll figure it out if you dont want to listen to me babel

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