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Old 06-16-2009, 04:48 AM
Boredomfiend Boredomfiend is offline
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Join Date: Jun 2009
Location: Long Beach, CA
Posts: 20
Default My First Build - and questions..

I can barely contain my excitement here, but since its 2:30am, I gotta force myself to chill. Today I put together my first kit, and tonight I got it running, and it was awesome.

I have plenty of tuning to do tomorrow... try to fix the kickstand, new cable cap and adjust the clutch cable and cable mod (pulley wheel), tune up the idle so it keeps running without throttle, replace the regular bike chain (snapped it, but it was old), change out the engine mount posts (screw china, I'm using stainless steel), remount the gas tank in a more permanent fashion, etc.

So obviously I have a nice task list for tomorrow, but I'm gonna love every minute of it.



Question though.. if I pull the clutch and slowly roll the bike, there is a little resistance and it sounds like the engine is pumping even though its not trying to start. Is this normal or just because my clutch cable isnt tight enough?

What does it mean if the engine seems tight? If I pedal to speed and drop the clutch, it slows me down without pumping the engine at all, then seems to "catch" once its a bit slower, and then the engine tries to start. Also if I'm going a little too slow and drop the clutch, it locks my back tire even if I have my full weight on the bike. Like I said, is the engine tight or something? When I first tested the engine mount with sprocket on, the bike would roll easily, pumping the engine, even without the clutch installed. Now it requires my full weight on the bike and sometimes even thats not enough. Whats the deal?

ALSO, from the initial gas fill, there's been air in the line. The tank has plenty, the valves are open, why wont it fill the line all the way? its weird seeing air in there. Do I just let it sort itself out, or is there something I need to do?
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  #2  
Old 06-16-2009, 06:26 AM
Bikeguy Joe's Avatar
Bikeguy Joe Bikeguy Joe is offline
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Join Date: Jan 2008
Location: Ashtabula county, Ohio
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Default Re: My First Build - and questions..

Quote:
Originally Posted by Boredomfiend View Post



Question though.. if I pull the clutch and slowly roll the bike, there is a little resistance and it sounds like the engine is pumping even though its not trying to start. Is this normal or just because my clutch cable isnt tight enough?

Very likely.

What does it mean if the engine seems tight? If I pedal to speed and drop the clutch, it slows me down without pumping the engine at all, then seems to "catch" once its a bit slower, and then the engine tries to start. Also if I'm going a little too slow and drop the clutch, it locks my back tire even if I have my full weight on the bike. Like I said, is the engine tight or something? When I first tested the engine mount with sprocket on, the bike would roll easily, pumping the engine, even without the clutch installed. Now it requires my full weight on the bike and sometimes even thats not enough. Whats the deal?

That all sounds normal for a new engine.

ALSO, from the initial gas fill, there's been air in the line. The tank has plenty, the valves are open, why wont it fill the line all the way? its weird seeing air in there. Do I just let it sort itself out, or is there something I need to do?

Keep an eye on it once you start riding the bike and see how it runs. Sometimes they will run fine with air in the top part of the fuel line. I would take out the fuel valve and make sure it is not obstructed with crud in the screen. Also check for good flow through the valve itself.
......................
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Old 06-16-2009, 06:45 AM
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Retmachinist Retmachinist is offline
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Join Date: Oct 2008
Location: Urbandale Ia
Posts: 634
Default Re: My First Build - and questions..

If you are going to change your motor mount studs, "Don't use stainless steel" Alot of people think stainless is really tough since it is hard to machine. It is not! Buy yourself some long, grade 8 allen head cap screws and cut off the heads to get the right lenght. They will be bullitt proof!
I only use stainless hardware for cosmetic purposes. For that it is great!

John
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Old 06-16-2009, 06:51 AM
Bikeguy Joe's Avatar
Bikeguy Joe Bikeguy Joe is offline
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Join Date: Jan 2008
Location: Ashtabula county, Ohio
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Default Re: My First Build - and questions..

Even grade 5 is better than what came with the kit...

I go to Home Depot and get the small bags of grade 5 metric fasteners, in various lengths, between 20 and 45mm and keep them on hand to replace ailing studs, ect.
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Old 06-16-2009, 07:10 AM
Forbisher Forbisher is offline
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Join Date: Dec 2008
Location: Orange County, CA.
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Default Re: My First Build - and questions..

Sounds like you need to adjust the clutch with the flower nut under the right side cover

There should be a little slack in the cable, not pulling on the arm

Did you regrease the gears around the clutch

If you full choke when the bike is running does the engine die right away?
You probably have an air leak

The studs in the Grubee kit are black oil hardened from Japan but still not as good
as american made thread

Stainless is not that strong
Mc master carr has very strong threaded 6 mm all thread
All thread you buy at Ace or elsewhere is not very strong too

Loctite the studs into the block as well as the exhaust studs

Put an inline fuel filter on and don't worry about the air in the line

There is a lot of tweaking to do to a new motor kit to get them running as
good as that red Felt # 71 Huskie that you saw at the El Dorado bike meet [SEE PIC]

It is using the same Grubee Starfire kit that you got from me

I rode it and it was one of the nicest motorized 2 strokes in terms of drivability I
have ever riden
Raully and John do the cleanest best running installs ......

A lot of the noise and roughness comes from the crappy sprockets, tensioner and
chain in the kit
The teeth on the sprockets especially the 10 tooth front are badly machined and
make the chain clunk....
Soon I will have a CNC machined front 10 tooth to match the rear and that really
smooths out the ride

PS: Thanks to Rockvoice for the pics from the bike meet
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Last edited by Forbisher; 06-16-2009 at 07:29 AM.
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