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1976 T3 to Le Mans Replica mini build

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Northern Bill:
I have been riding the bike for a while now and I have a few things that are unresolved.

1. I have checked the carbs for air leaks, checked the cables and springs, checked the advance on the distributor and everything seems to be good yet the rpms continue to drop very slowly, especially in the higher gears at over 4000 rpm. All seems to be well on idle and in first and second. In third if I am going along at 4000 rpm the bike acts like it is on cruise control ifI ease off the throttle but if I  twist the throttle back quickly the rpms drop a little faster.  The two 36mm carbs appear to be almost new.

2. I have a spot of fresh oil collecting on the top of the crankcases between the barrels. I wonder if this oil is coming from a breather pipe.

3. When I look at the bike from the side the mistake I made on the gas tank paint makes the front of the bike look like it is sitting higher but I also wonder if the bike is sitting higher.  Do you think pulling the fork tubes up through the triple clamps a half inch might help?

To your point No 1: have you checked the condition of your throttle cables? Do your throttles snap shut if you open them and let go, with the engine off?
If they are sticky, are they routed correctly?

Nice build!

As for the bike sitting too high: Its a matter of taste but have a look at the bottom rails. I would think it would look more "mean" if you lower the front enough to keep them horisontal. On the other hand, the front springs are typical quite soft so the bike may look low on load.

I have mouted 36mm PHF on my SP1000 too. I found them a bit difficult to deal in and had starving issues too. What I propose you to do the following in this order:

1: Check for clogged internal tank filters. Mine were covered with some red stuff (rust) from years lack of cleaning. I cleaned the tank and put new filters in. Symptoms were it ran fine with full gas tank but was starving when I get below half full.....

2: Check for correct float level. Should be 18mm measured like on Fig 13:

3: Make sure you have the right needle valve. I went from 250 to 300 and it gave a better flow.

4: What jets are you running? I found it hard to find a recommended combo for a SP1000 but with mine (including Lafranconi Competitione and K&N filters) I use 70 Idle, 140 mains (should probably be 135), AR268 atomizers and K18 needle, second lowest clip position.

If you use standard Lemans Manifolds there may be a step from the end of the manifold to the heads, around 1,5mm I think as the heads are 34mm at the end. It may not be a big deal but could create some turbulence?. I use a special made manifold with conic internal shape to overcome this step, got them from This is though more icing of the cake and should not create the issues you mention IMO

Northern Bill:
After riding the Guzzi for a while I decided it just wasn't for me.  I think I have made the transition to light bikes only. With the Guzzi sold I now own 2 two fiftys and 2 five hundreds and the heaviest one is about 350 pounds. My newest bike, a 2010 Kawasaki Super Sherpa weighs in at 280 pounds wet. Despite losing a bit of money on the T3 project I enjoyed the build and really liked the look of the finished product. I would definitely do it over again but being honest with myself I just enjoy riding my smaller bikes more. Thanks again for giving me advice along the way.

Although I have sold the bike, the build is not over because the new owner is having the bike painted professionally and he is having the rear wheel respoked.  He is going to take the bike to the next level.  When I see it next I will be salivating all over it!


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