Swapping gearing from an '82 engine into an '83 engine?

[mcgovern61]

I built a Harbor Freight Tag A Long trailer for my 1100. So far, it tows great but I have noticed it takes a bit more RPMs at higher speeds to not lug the engine.

My bike is technically an '82 with the original '82 wheels and final drive, but it has an '83 engine in it which reduces my RPMs at highway speeds very nicely! BUT, that same reduction in RPM is causing the engine to come under a load pulling the trailer.

I originally had an '81 engine in the bike. When I had the '81 engine in this '82 frame I used the '82 final and ran about 5000 RPM at 70 MPH. Swapped in this '83 engine and now it runs a little over 4000 at 70 MPH. My guess is the '82 is right in between.


I still have the '81 and '82 gears and all internal components. My question is, is it even feasible to swap out the '83 and '82 gears if I decide to split the cases next Winter?

I am assuming everything lines up and it should only be a matter of tear down and reassemble?

Thoughts? :headscratch:

 

[Steve83]

Bearings, shift forks and drum are the same. You'll need to change the entire set, including the output shaft gear, and it will work. My '83 bike has an '82 case, '80 crank, '83 transmission, '77 carbs...it's a pretty mixed up combination - and it runs sweet! It's still not registered, so I don't ride much, but Dan rode it, and seemed impressed.

 

[slabghost]

Gearing might be fine with 75-77 cams and C5. Cheaper to use the lower gears but more power will help the gearing you have.

 

[mcgovern61]

C5 keeps coming to mind. I will be talking to Brian more this weekend about his C5 and trailer experience!

 

[joedrum]

i would not give up 83 gearing for a trailer ....put on weber carb along with c5 and your problems are over

 

[dan filipi]

What about all the times riding without a trailer?

 

[ekvh]

"Bearings, shift forks and drum are the same. You'll need to change the entire set, including the output shaft gear, and it will work. My '83 bike has an '82 case, '80 crank, '83 transmission, '77 carbs...it's a pretty mixed up combination - and it runs sweet! It's still not registered, so I don't ride much, but Dan rode it, and seemed impressed."-

------Steve83, now that's my kind of bike.

 

[slabghost]

Add C5, 75-77 cams and nice single carb dialed in and i'm all for it!

 

[mcgovern61]

dan filipi » Wed Apr 08, 2015 7:43 am[/url]":35xkra2y]
What about all the times riding without a trailer?

Good question. I suppose the answer lies in how much I use the trailer. It is my opinion that most of my longer rides are going to include pulling the trailer. Around town and country road rides the RPM gets just a bit too low at 55 MPH. I am constantly shifting from 5th to 4th on the country road rides here in New Jersey because the speed limit averages 45 - 50 MPH. In 5th gear, that is right at 2800 to 2900 RPM, the point where my engine starts to load up. I don't like riding around in 4th gear for long periods.

Again, maybe the C5 is all I really need?

 

[slabghost]

it'll make a big difference.

 

[dan filipi]

Well I'm not going to say C5 is going to be the end all of your troubles but it will help.
The combination of C5 and a weber does very much increase available low end torque and responsiveness.

 

[backlander]

What size rear wheel is on it ? Your already running the lowest geared rear punkin at 3.1 and theres not a whole lot of difference in the trans gears from what I see. Might be an easier task to go to a 15 rear wheel.

 

[mcgovern61]

I have the '82 16" rear wheel.

It looks like the primary difference between the '82 gearing and the '83 gearing is the secondary transmission reduction. For the '82 Standard, it is 0.973 and for the '83 Standard it is 0.897. The rest of the gears (except 1st) are the same including the final drive ratio.

 

[joedrum]

yes first gear is wnat makes the 83 what it is if you want 82 final gearing for hiway pull drop to forth ....its about a one gera difference and the first gear on 83 trans is lade different to compensate for take off ...chart shows the difference

 

[backlander]

joe, can a 1200 rear wheel and flange be adapted to the 1100 punkin ?

 

[joedrum]

no ...as i see mike ..ive been wrong before though but i did look at it ..punkin and wheels lap different and just no way

 

[backlander]

Ok, thanks for checking joe. !! Wonder if they made a custom wheel or a Lester in 15 in that would work on the 1100. I have no idea myself, just seems it would be easier to lower the ratio by swapping out to a smaller rear wheel than pulling engines and splitting cases.

 

[Ansimp]

:0fftopic: Has anyone else noticed that Gerry has managed to organise a great trailer that is now justifying a C5 ignition while helping his daughter move home? :yes: :clapping:

 

[joedrum]

lol

 

[mcgovern61]

Ansimp » Wed Apr 08, 2015 5:14 pm[/url]":1rh58s9g]
:0fftopic: Has anyone else noticed that Gerry has managed to organise a great trailer that is now justifying a C5 ignition while helping his daughter move home? :yes: :clapping:

Its all part of a formidable plan.......... :smilie_happy: