Engine runs kinda "lurchy"

Andyinchville1 · #11 (**permalink**) 08-15-2008, 11:21 PM

HI,

Wow....5 to 8 MPH?.....You'll probably have to go pretty large to have the engine run without lurching at that speed.....The largest sprocket for a motorized bike I have made so far is 65T (we can go lager if needed) for a fellow that wanted to ride his bikes on trails in the woods....

Andrew

Radmanfly · #12 (**permalink**) 08-16-2008, 12:07 AM

Regarding your muffler crank interference issue...during the test fitting of my engine (while fabricating the front mount) I noticed that the muffler would hit if the engine was not perfectly aligned with the seat post (rear mount) and if the front was too high (i think), the muffler would interfere. I tried different heights along the seat post and made the front mount to accommodate the position that fit the best which turned out to be as low as possible but still straight with the seat post (parting halves of rear mount aligned to seat post) See pics!
Considering how many interference problems I have seen on here, maybe I just got lucky and the pipe I got happened to be bent right.

deacon · #13 (**permalink**) 08-16-2008, 07:34 AM

Ride the bike if it isn't too awfully bad and it will smooth out as it breaks in. I had that problem for the first hundred miles now I just don't notice it if it is still doing it. I think most of us are a little paranoid at first. We think the bike is going to explode any minute. Why wouldn't it after all we did the installation lol.

Nomad · #14 (**permalink**) 08-16-2008, 07:50 AM

Quote:

Originally Posted by deacon

Ride the bike if it isn't too awfully bad and it will smooth out as it breaks in. I had that problem for the first hundred miles now I just don't notice it if it is still doing it. I think most of us are a little paranoid at first. We think the bike is going to explode any minute. Why wouldn't it after all we did the installation lol.

Deacon, thanks for the reply, that's funny, but you're right, I do think it's gonna explode any moment. When I ride it there are times when going slow is appropriate, and I keep forgetting this is a "manual clutch driven" thing.. so feathering the clutch is a good tip from "Pedalpower".. thanks alot for the words of confidence..
regards
Bob

Nomad · #15 (**permalink**) 08-16-2008, 08:03 AM

Quote:

Originally Posted by Radmanfly

Regarding your muffler crank interference issue...during the test fitting of my engine (while fabricating the front mount) I noticed that the muffler would hit if the engine was not perfectly aligned with the seat post (rear mount) and if the front was too high (i think), the muffler would interfere. I tried different heights along the seat post and made the front mount to accommodate the position that fit the best which turned out to be as low as possible but still straight with the seat post (parting halves of rear mount aligned to seat post) See pics!
Considering how many interference problems I have seen on here, maybe I just got lucky and the pipe I got happened to be bent right.

Thanks Radmanfly, I will pay particular attention to the fitment on the next one I build, OH yes I will build another one maybe more... your bike looks like the "Black Bart" of motorbikes, cool.....