Author Topic: CB 836cc f1 turbo - spoked kickstart street turbo (Read 80701 times)

NitroHunter · « **Reply #225 on:** August 20, 2016, 06:18:16 PM »

As I remember, the Dragbike Comp Eliminator rules gave me 36 degrees rake and about 6" longer wheelbase. I'd had Kosman build a torsionally braced 6"longer unit - with mounts for a 2-1/2lb N2O bottle - when I had the Cobra motor as my daily toy, so it was just right for this using a little 7" slick on that scrawny (by today's standards) Mitchell wheel. Back then all my roadracer buddies had this size set-up with with PZ2 compound tires on their track bikes, so that's what my hot rod had too, and I can personally attest to their safety at 3x the legal speed limit.
I had the front end raked by a local fabricator named Dick Washer. Yeah.
It would run straight as a string, but turning was more like riding a chopper. Leaning was everything.

Ilja · « **Reply #226 on:** August 21, 2016, 10:18:20 AM »

Installed the frame kit and made an additional crank vent at the top cap!

Ilja · « **Reply #227 on:** August 21, 2016, 10:23:50 AM »

754 · « **Reply #228 on:** August 21, 2016, 11:34:14 AM »

What a mean looking bike, the oldgold paint looks so cool on it..

Ilja · « **Reply #229 on:** August 23, 2016, 04:19:43 AM »

Noticed something "strange" about the K7/k8 manifolds...
From left to right they seem to get longer ? And spacing is roughly 77- 80- 72mm.

Are the k7/k8 carbs not symmetrical or something?
By the way, they are 40mm on the carb side and not 38mm like I wrote earlier.

Anyways, busy with re-arranging the spacing of my carbs and making adapters for the connectors between the carbs and for the 38-40mm difference.
Can't wait to fire it up....

madmtnmotors · « **Reply #230 on:** August 23, 2016, 04:41:03 AM »

Quote from: Ilja on August 23, 2016, 04:19:43 AM

Noticed something "strange" about the K7/k8 manifolds...
From left to right they seem to get longer ? And spacing is roughly 77- 70- 72mm.

Are the k7/k8 carbs not symmetrical or something?

Are you using aftermarket manifolds? I noticed the same thing with the aftermarket manifolds I'm using. I have not tried to compare them to the original stock rubbers, but I did have to open up the hole in the air cleaner hanger bracket just to get the stock air cleaner bolted up. The aftermarket manifolds I'm using seem to push the right side (#4) another 1/4" (6 or 7mm) away from the head. I think the aftermarket source for the carb manifolds might have used the K8 manifolds for 1 & 2 while using the F2 manifolds for 3 & 4. I think the F2 manifolds were just a little longer? I might have some original K8 and F2 manifolds to compare, but I may not be able to tell them apart since they likely reside intermingled in the same box!

I thought about buying two sets, then using the 1/2 from both sets (flipping one pair for 3/4), then seeing if the 3/4 from both sets matched up with the F2 (again, flipping one pair of the 3/4 to use on 1/2).

Ilja · « **Reply #231 on:** August 23, 2016, 05:35:13 AM »

Yes mine are aftermarket! They are not available original I think... or maybe only 1 & 3.

At first I bought 2x 1 and 2x 3 BUT this doesnt work!!! The manifolds are not symmetrical and slightly angle the carbs to horizontal alignment.

So I had to buy the 2 & 4 and now stuck with two extra manifolds...

25 euro per piece.

I think your right about them mixing up K8 and F2.... because also the opening is 40mm (f2 carbs?) instead of 38mm (k7/k8 carbs?).

madmtnmotors · « **Reply #232 on:** August 23, 2016, 10:40:07 AM »

Quote from: Ilja on August 23, 2016, 05:35:13 AM

Yes mine are aftermarket! They are not available original I think...

That is correct. Aftermarket is the only source I am aware of.

Quote from: Ilja on August 23, 2016, 05:35:13 AM

At first I bought 2x 1 and 2x 3 BUT this doesnt work!!! The manifolds are not symmetrical and slightly angle the carbs to horizontal alignment.

I suspected this to be the case.

scottly · « **Reply #233 on:** August 23, 2016, 06:06:37 PM »

I've got a set of original K7 carb to head rubbers I can take pics and measurements of, if that will help.

Ilja · « **Reply #234 on:** August 26, 2016, 03:24:35 AM »

Inter-Carb fuel and air connectors.

Ilja · « **Reply #235 on:** August 26, 2016, 04:10:06 AM »

Yay!

Ilja · « **Reply #236 on:** August 26, 2016, 07:10:55 AM »

38-40mm adapters....

Ilja · « **Reply #237 on:** August 26, 2016, 08:16:00 AM »

Nice n toight!

Bill/BentON Racing · « **Reply #238 on:** August 27, 2016, 01:37:59 PM »

Good job! Looks great, Bill

Ilja · « **Reply #239 on:** August 27, 2016, 03:00:40 PM »

Thanks!

Tomorrow testride!!
(If everything goes well..)

Ilja · « **Reply #240 on:** August 28, 2016, 04:57:07 AM »

Is there a way to upload videos directly?

Bike runs super smooth and idles at 1000rpm! Those new chains really made a big difference!
Taking it out for a ride this afternoon.

Ilja · « **Reply #241 on:** August 28, 2016, 05:24:04 AM »

Phone mic doesnt do it justice, but its really really smooth..

Bill/BentON Racing · « **Reply #242 on:** August 28, 2016, 06:33:41 AM »

Way cool, keep us posted, Bill

Ilja · « **Reply #243 on:** August 28, 2016, 07:31:40 AM »

Yay testride went well!
Bike runs flawless and I notice exactly 0 difference with before regarding off-boost torque and spooling, maybe it spools even earlier.
Did some pulls up to 0.8 bar and couldnt notice any pings or strange noises at 5000-6500rpm like before.... so far so good!

Now I need to try and keep myself from hammering the engine with lots of boost before breaking it in properly lol.

And I need to decide if I want to have the intercooler on or not.. its worth testing I think..

I will see if I can make a vid on the bike..

turboguzzi · « **Reply #244 on:** August 28, 2016, 08:01:37 AM »

hei ilja
kudos on the work, looks like you are getting there with development!

somewhat unrelated question seeing that you run CVK carbs. do you have a source for adjustable needles for these? i am running a set of 32 CVK carbs on a z750 kawasaki, they come from a zzr600, but needles are only "one position", no grooves... would be nice to find CVK needles with 5 grooves for fine tuning.
tnxs

Ilja · « **Reply #245 on:** August 28, 2016, 09:35:30 AM »

Quote from: turboguzzi on August 28, 2016, 08:01:37 AM

hei ilja
kudos on the work, looks like you are getting there with development!

somewhat unrelated question seeing that you run CVK carbs. do you have a source for adjustable needles for these? i am running a set of 32 CVK carbs on a z750 kawasaki, they come from a zzr600, but needles are only "one position", no grooves... would be nice to find CVK needles with 5 grooves for fine tuning.
tnxs

Tnx! Just did another 50km and everything looks to be fine. Running 0.7 to 0.8 bar now.
Engine feels solid... you dont need to rev it up high to go very fast like the stocker so its a very smooth bike. Midrange torque between 5000 and 7000rpm is huuuge. (Didnt go above 7 yet, break in and too much speed for license lol).

My carbs also came from a zzr600... they had dynojet needles installed with k&n pods at first. Those needles had 5 clip positions but were way too rich for the cb turbo.
Im running stock zephyr 750 needles at stock position in the cb!

You can also put some small washers underneath them to adjust!!

MessnerMoto · « **Reply #246 on:** August 29, 2016, 02:12:50 AM »

Nice work. Congrats on the running engine

754 · « **Reply #247 on:** August 29, 2016, 07:38:06 AM »

If you are stacking washers under the needles,check them with a micrometer.
Most are stamped and have a slight curl or burr on one edge...which should be removed..by file or emery.
(much like some of our steel clutch plates have )
Stacking several together with burrs the wrong way, could get uneven heights.

Ilja · « **Reply #248 on:** August 29, 2016, 08:58:41 AM »

Quote from: 754 on August 29, 2016, 07:38:06 AM

If you are stacking washers under the needles,check them with a micrometer.
Most are stamped and have a slight curl or burr on one edge...which should be removed..by file or emery.
(much like some of our steel clutch plates have )
Stacking several together with burrs the wrong way, could get uneven heights.

True! And its pretty critical...
I have used maximum of 2 so not that bad but with pods you will need more on some bikes.

turboguzzi · « **Reply #249 on:** August 29, 2016, 09:26:13 AM »

Quote from: Ilja on August 29, 2016, 08:58:41 AM

Quote from: 754 on August 29, 2016, 07:38:06 AM
If you are stacking washers under the needles,check them with a micrometer.
Most are stamped and have a slight curl or burr on one edge...which should be removed..by file or emery.
(much like some of our steel clutch plates have )
Stacking several together with burrs the wrong way, could get uneven heights.

True! And its pretty critical...
I have used maximum of 2 so not that bad but with pods you will need more on some bikes.

yep, indeed

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Author Topic: CB 836cc f1 turbo - spoked kickstart street turbo (Read 80701 times)