what did you do to your motorized bicycle today?

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mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Re: what did you do to your motor bike today?

That head is made by Jim " Manic Mechanic " here is a link to a dealer High Comppression Billet Head for GT5 and PK-80

They show to be out of stock right now.....dang-it I was woating one too!



KCvale : Who makes that head?


I got my sport exhaust in the mail today (yay!), and it's a perfect fit. I also got some quick disconnect clips and crimped them on my wires, killswitch was intermittent and only worked when I squeezed the clump of wires wrapped in black tape, so I put a new end bit on my ground wire, it was almost sheared off. I'm going to stress test it later, but gf just got home from work, so it'll be a couple hours till I get bike time.
 
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mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Re: what did you do to your motor bike today?

I did some porting, gasket making & head & jug shaving on one of my engines today, I pulled the top off, Head, Jug, Exhaust, Intake, Carb.

I polished the transfer ports pretty good and smoothed up the intake and exhaust by removing all those typical burrs that are always in the ports of these engines, I then port matched everything real nice and made a new intake gasket for the Billet Manic M. intake I put on it, I also smoothed up the inside of the exhaust lead off pipe for the SBP expansion Chamber I put on it, it had some over penetrated welds on the inside that needed ground out.

I also shaved .002 off the jug deck and shaved .006 off the head, I made a new head gasket out of .016 Alum. which is .011 thinner than the .027 gasket that was on the engine when I started the mods today.

I started on it at about 1:30PM and had back together and running by 8:00pm, took it for a very short ride just up the road and back, but it was getting dark so I couldnt really open it up to see if what I did helped the top end or not, but I could tell it has a much better throttle response than before.

Now if it just helped the top end a bit Ill be happy, it was topping out at 31MPH with a 34T sprocket which was pretty weak compared to my other bikes which will hit 37mph & 39mph with larger sprocket a 41T & a 36T.

I'm still not convinced that the SBP expaansion chamber isnt some of my trouble on top end, I may be getting rid of that baffle on the back of it and putting my own muffler back there like the one I rigged up on one of my other bikes, just need to do some more testing in the next few days and see what I come up with.....

Peace
 
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ToxicAz520

New Member
Mar 11, 2011
288
0
0
Tucson,Arizona
Re: what did you do to your motor bike today?

nothing to my bike but did finally get my gt lts-5 from fedex today so i am happy gonna put it together tonight and start preping it for my build i cant wait i will take pics and document the process i am really excited about he build
 

sketchman

New Member
Mar 23, 2011
168
0
0
WV, USA
Re: what did you do to your motor bike today?

Got it running, and got "The look." from my neighbors. I'm the only one in my area. Poised to make $$$ WHEN gas goes to the moon. :) Oh yeah.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Re: what did you do to your motor bike today?

Took my bike that I did all the work too yesterday out this evening when I got home from work and took it for a 4+ mile ride, I didn't have my GPS mounted on it, but I can definetly tell the work I did made an improvement in the top speed, I wont know anything for sure until I get the GPS on it for a accurate speed check but I'm taking a wild guess and saying it improved by at least 3-5MPH maybe a couple more, it is twisting up to a higher RPM than it was for sure, and doesn't have that flat spot where it did before, I have my fingers crossed and am hoping for at least 35-36MPH top end now with a comfortable cruise speed in the 30-32MPH range, If I have time tomorrow evening I will pull out the GPS and know for sure what I have.

Happy & Safe Riding all.......

Peace
 

ToxicAz520

New Member
Mar 11, 2011
288
0
0
Tucson,Arizona
Re: what did you do to your motor bike today?

started putting together my full suspension frame today getting it ready fot the motor that should be here tomarow but probably wnt get to ride it till i get enough money for a shift kit from sbp it is more expensive then my gt lts from and motor combined
 

Blazecc

New Member
Apr 19, 2011
66
0
0
connecticut
Re: what did you do to your motor bike today?

so i put a billet intake boost bottle ready on my carb,today it ran fine for a few then gas was puoring out of my aftermarket adp air filter. i did notice the gas line was a little oversized and was also leaking a bit so i replaced that and the problen still persists
 

DaveC

Member
Jul 14, 2010
969
1
18
Boise, ID
Re: what did you do to your motor bike today?

Pulled all the parts off the bad 66 and installed them on the new 49. I spent a while sanding the jug where it wasn't machined. Got it nice and flat. I also sanded the taper on the bottom of the jug to make it easier to slide the rings in. Made sure the edges around the ports were rounded. Tapped all the holes then cleaned and white lithium greased the piston and jug. Slid it all together. Screwed in the head studs and installed the Puch head.

I thought the new front mount was going to be trouble but it actually is better now. The narrower mounting holes required me to "massage" the tube with a hammer but now it fits much better than the old wide clamp.

I can't figure out why it sits higher in the frame, though. That's ok but there a place on one of the back struts where the chain passes real close. I have a pad cut from a tire there now and that has kept the chain from cutting but I'll have to use a piece of conduit or something as a sacrificial piece to keep from damaging the aluminum strut. I'm thinking about a 50 tooth sprocket to take the place of the 56.

Wiring and chain then I'm off and hopefully running.brnot
 

ToxicAz520

New Member
Mar 11, 2011
288
0
0
Tucson,Arizona
Re: what did you do to your motor bike today?

Just got a txt from my wife sayibg that. My starfire motor came in so I gonna start buildin my bike wen I get home and I off tomarow I will tke pics and start a thread for it
 

ToxicAz520

New Member
Mar 11, 2011
288
0
0
Tucson,Arizona
Re: what did you do to your motor bike today?

If I dnt have all the parts to get my new build going this weekend I will mount it on my cruiser for break in
 

DaveC

Member
Jul 14, 2010
969
1
18
Boise, ID
Re: what did you do to your motor bike today?

so i put a billet intake boost bottle ready on my carb,today it ran fine for a few then gas was puoring out of my aftermarket adp air filter. i did notice the gas line was a little oversize and was also leaking a bit so i replaced that and the problen still persists
That sounds like there's something in the float needle seat area. If you not familiar with the procedure start with removing the carb and draining the gas. Remove the float bowl. Turn upside down, there's the float. At the hinge there is a pin, remove it, it should almost fall out. There is a small wire clip connected to the needle, it should come out with the float. The needle seat has a slot for a screwdriver, remove it. This part clean it out and look through it, there should be no obstruction. Then check the tip of the needle valve. It's made of fuel proof rubber and sometimes it can have a bent tip or cracks. Look up inside the opening where the valve seat goes for stuff in there, if you have a air compressor or canned air try to blow it out. Avert your eyes doing this, you could get a gas back-blast.

Now that you've done all you can put it back together in reverse order. A quick float level check is to have it up-side down with the float closing the valve. If the float is parallel with the float bowl mounting flange then it's pretty dang close.

One other thing to check first is if you have a tickler is it hanging up? It holds the float down so extra gas goes in to help it start.
 

RebelHellbilly

New Member
Apr 22, 2009
222
0
0
Salisbury,North Carolina
Re: what did you do to your motor bike today?

been awhile since i posted...been having sum issues..sum MB wise others well...its life. the fix i did last weekend came apart sunday. i purdy much tore down the top end. had thought about having sum drill and re-tread the stripped exhaust hole. but having further inspecting the jug..i noticed a chipped mark on the sleeve. so i ordered a new 1 off ebay on monday. should have it tommrow. and got new rings,fuel valve, needle bearing. got those today but realized i order a crank bearing...so i had to order the 1 for the piston wrist pin...if all goes ok...hopefully have my china girl back buzzing by tuesday? gotta wait N see...kinda suks not riding..been having withdrawls N all
 

ducedave

Member
Apr 17, 2011
370
4
18
Mentone Ca.
Re: what did you do to your motor bike today?

replaced 5 spokes shimmed 3 of the 5 spoke holes wire wrapped where the spokes where they crossed, rim is stronger that way
 

ToxicAz520

New Member
Mar 11, 2011
288
0
0
Tucson,Arizona
Re: what did you do to your motor bike today?

got my starfire gt4 today and was all excired wen i got hone home from wrk to start my build and opened up the box and the gas i scratched waht the h*** that sucks its supposed to be brand new and nice isnt it?
 

DuctTapedGoat

Active Member
Dec 20, 2010
1,179
10
38
38
Nampa Idaho
Re: what did you do to your motor bike today?

S*** happens when you have something manufactured at a site with little to no quality control, it travels 7000 miles and goes through a few distributors hands.
 

turbojoe

Member
Mar 30, 2011
57
0
6
Little Rock,AR
Re: what did you do to your motor bike today?

WHOW :eek: What in the world happened?
I don't know. I just noticed the wheel was loose and I pulled it off to tighten it up a bit. These were stock wheels on a Micargi bike I bought a month or so ago. I have a shift kit on the bike so I don't know if that puts more torque on the wheel or if the axle was a little bent to begin with.
 

chrisme

New Member
May 30, 2009
423
0
0
Maine
Re: what did you do to your motor bike today?

Stripped my bike down to get it ready for the new engine. I can't afford gas, so that got my butt moving to drop a new engine on the bike.
 

Skarrd

Member
Oct 13, 2010
501
2
18
34
Chandler, AZ
Re: what did you do to your motor bike today?

yesterday (since i was too tired after to post here XD )
broke the jack shaft to crank chain AGAIN!

went to the bike shop and got some bmx half link chain. can't wait to see how strong it is. i put it on the engine to jackshaft, and jackshaft to crank. have 4 links for spares XD