New member with a question

[rphrider]

I just got a new to me 1965 Bridgestone sport 90 and am having a problem I could use some help with.
I put in fresh gas 20:1 and the bike was hard to start. Once running it will run for about a mile or so then bog down and stall in 3rd or 4th gear. When this happens the only way I can restart it is to role start it then it will run rough for about 15-30 seconds then run fine for another mile or 2 then the same thing happens. I would appreciate any advice I can get. Thanks, Kevin

[old smokey]

My first thought would be poor fuel supply. Maybe it's got a full carb bowl of fuel to start and then the fuel demand for riding depletes it. Can you try running it with an external fuel supply to the carb and see if it sustains good rpms for a few minutes on the stand?

[rphrider]

Thank you for the advice. I think it is starving for fuel. It will run for a long time in 2nd gear at low speed, but after I get going for a mile or two in 3rd or 4th it sputters and dies. It wont kick start I have to roll start it to get it going.
This may sound stupid, but is there a vent on the tank or in the gas cap?  I don't think it has the original type petcock in it.
I will try an external fuel sorce and let you know how it works out. Thanks again.

Kevin

[Bikenstein]

You can loosen your gas cap to provide venting for a test. You can also remove your float bowl, turn your petcock on and see if fuel is flowing well. If not back track from there. If it is flowing well, I would tend to think it's a thermal type of electrical problem or something shorting out but giving strange symptons. Sounds like a fuel problem though. I've learned a long time ago not to get carried away in my thinkin. Imagining all kinds of oddball scenarios.  What was I talkin about?   Oh yeah fuel. Probably a dirty petcock  Welcome to the site Kevin Check out the manuals section and download what you need if you don't have one. Richard has original parts

[rphrider]

Thanks for your help! The fuel is only trickling out of the fuel line from the tank. The Petcock has been "modified" buy the previous owner.
I think that is my problem. I am going to try to get a new one.

Kevin

[BRT-GTR]

Kevin,
        Before you get a new one try taking the petcock off the bike, take it apart and clean out all the passages including the brass tubes on the top. May have to remove gauze filters but they are usually in poor condition after all this time anyway. A metal rod 4mm, I think,  with a flat srewdriver type point will clean out the brass tubes, just work/spin it down slowly withdrawing often to clean off the gunge.. Solder up some new filters and reattach. Hey presto one working fuel cock. You dont say what the 'mod' is.
Good luck, Brian the Brit

[Bikenstein]

Kevin, from the way you describe it  runnin, you need to go ahead and clean your carb good, too. I'd also check the points, plug, and timing if that hasn't been done recently, to get her runnin like she should.

[reed]

Kevin,
On my Bridgestone 90 and 100 i just got new fuel taps from Richard.
And just do what Bikebstein said clean your carb check your points
I would fit new points, timing and plug and clean the baffel in your
Exhaust and go from there.
Thanks.
Steve.

[rphrider]

Thank you for your advice! I got a new fuel tap from Richard. It was well worth the $35. I put it in and got fuel to the carb,
It started up but would stall and be hard to restart. I got a new correct NGK B7HS spark plug, set it to the right gap and it made a huge difference.The bike is running great. I still have not set the timing, cleaned the carb. or changed the points. I have not had much time to tinker with it. The next thing I am working on is the lights don't work. I took out the battery and it is dated 1969! The fuse is good and I have power to the terminals when the bike is running. I plan to get a new battery and see if I have power to the lights, maybe bulbs are blown?
You can see the bike running at  http://www.youtube.com/watch?v=iu8HLuE7g4I.#
I have finally got to ride it! I bought it because I thought it was cool, but at 6'1'' 250+ I feel like a gorilla on a trike,LOL. Decided to sell it and get something bigger.

[Bikenstein]

Sounds perty good! When you rev it, looks like you have one of those combination speedo/tach units

[disc_valve]

Hi, Rphrider.

You could well have blown bulbs in the lights. However... the Bridgestone singles have Flywheel magnetos, and the lights are powered directly from the magneto lighting coil, and not from the battery. So a knackered battery wont stop the head and tail lights working. You do, of course, have to have the engine running to get lights. The only electrics powered fropm the battery are the stoplight. neutral light and horn.

Hope that helps,

Graham

[rphrider]

Thank you all for your help!T he bike sold today to a 60 YO man who had the same one same color when he was 14! I feel like he was meant to have it.