Boygofast 47mm sleeved cylinder info

U

User 27079

Guest
ok.
I've been running WOT @33mph then back down to 27mph, just riding most of the day for an hour or so then taking a break
for 10minutes then going again.
At 10 am i drained my gas tank and added fuel mixed @ 5oz per gallon.
I was using 6.5 oz of oil lol i know...i know... go ahead and say it :D

I drive pretty much slow like 18mph up to and through 29mph just cruisin.
I know that i have the bottem end oomph to get up these hills here, so as long as it holds up @ 25-30mph and
stays a hill eater i'll be happy.

Now, my neighbor has a machine shop a few doors down from me and i talked to him today.
He said he can and will pin the cyl to the sleeve for me, keep yor fingers crossed.

Ride Safe! :)


HP
 


U

User 27079

Guest
I think it's to soon and the cold weather isn't helpin any but i think this bgf
sleeved cyl if pinned and possibly honed to perfection is a good deal.

I changed/re-routed the expansion chamber set up today as well,here are some pics:

IMG_20190203_214223 - Copy.jpg




IMG_20190203_214116 - Copy.jpg




IMG_20190203_214614 - Copy (2).jpg


I haven't checked the second cylinder yet.
I'm going to give it 500 miles then check it.

Everything seems to be ok.

When i changed the fuel mixture i noticed an increase in acceleration and low rpm power.
I also had to regap the plug for some reason and I think i may have to re-jet, I did notice some 4stroking.

Ride Safe! :)


HP
 
U

User 27079

Guest
So today on the way to work i heard what sounded like detonation i guess or is that pre detination?

I have been running the 6cc Fred head for over a year now and never heard this.

I took the head off and other than a small leak i didn't see any pitting on the head or the piston.
I'm confused, what's going on?

I have not upjetted as of yet though, could that be it?

So i put a thatsdax RT HEAD M8 on and it seemed to actually stop.
What causes this and should I go ahead and fatten up the jetting a bit or just keep on goin?
The only difference in the head that is visibly noticeable is the dax head has no gooves/rings to seat into the head gasket,
while the Fred head does.

Strange! o_O


Ride Safe! :)

HP
 

JerboaJohn

Well-Known Member
Joined
Jul 29, 2018
Messages
900
sound of pre-det? with no changes and it ran a year fine, maybe what your hear is piston slap or bearing wear. if it sounds really uncool, you'll have to look at the jug, piston and see if there is any up n down play on the rod, both at the wrist pin (needle bearings can fail) and mains. see if any play.
but it didn't feel different or loss of power? just the sound?
maybe it's not jug related and could be coming from the clutch or bevel gear = easy to check
 
U

User 27079

Guest
sound of pre-det? with no changes and it ran a year fine, maybe what your hear is piston slap or bearing wear. if it sounds really uncool, you'll have to look at the jug, piston and see if there is any up n down play on the rod, both at the wrist pin (needle bearings can fail) and mains. see if any play.
but it didn't feel different or loss of power? just the sound?
maybe it's not jug related and could be coming from the clutch or bevel gear = easy to check
After a 20min ride it came back with the dax head, so i took the head and cyl off,
on the BGF cyl there was a small groove just through the sleeve onto the actual alum. cyl.
So i got the glass and wet dry sand paper out and seem to have gotten rid of it.
It looked as though gas was escaping just enough through that groove to make a popping noise, and affect the power.

I just put everything back together and rode it again.
Geez!
Everything is going smoothly so far.
Plenty of hill climbing power and got up to 31mph pretty quick.

I think i am gonna take this other bgf cyl to the machine shop and have them check it for abnormalities where the head contacts the sleeve and alum.cyl.

Ride Safe! :)


HP
 
U

User 27079

Guest
sound of pre-det? with no changes and it ran a year fine, maybe what your hear is piston slap or bearing wear. if it sounds really uncool, you'll have to look at the jug, piston and see if there is any up n down play on the rod, both at the wrist pin (needle bearings can fail) and mains. see if any play.
but it didn't feel different or loss of power? just the sound?
maybe it's not jug related and could be coming from the clutch or bevel gear = easy to check
Everything else seems to be the same as always.
I hope it was just the popping of that little bit of gas escaping.

Right now after the last ride everything seems to be back to normal.

Keep yor fingers crossed (y)



Ride Safe! :)


HP
 
U

User 27079

Guest
Burnt through a tank of gas today.
I think things are coming together.
Rode up some monster hills today @ 24mph so the hill climbing seems to be back or increasing.

I like those rings @SP

I have about 200 more miles to go until i hit the 500 mile mark.
Then i'll tear it down and take some pics.

On the other bgf sleeved cyl i widened and hightened the exhaust port, just waiting to change the cyls out @500miles.

Ride Safe brothers & sisters! :)

HP
 
U

User 27079

Guest
@Spare_Parts I just wanted to take the time to apologize to you about hijacking your topic/thread.

I get excited at times and go overboard.
I hope ya accept my appology man :)

Ride Safe!

HP
 

Spare_Parts

Well-Known Member
Joined
Nov 29, 2017
Messages
1,168
Haha don't worry about it. Happens all the time on the forums. That's why I'm updating the 1st post.
 
Top