A Labor of Love; aka building a Rocket III Speedster

Finally found the manufacturer of the screen I was using, this one:
20230811_224921.jpg

I bought it 2nd hand from a French Captain on ebay, but motoplast is smart enough to embed their business card on the inside of the fiberglass area and I had the foresight to take a picture before I painted it, finally found the picture.

motoplast-gregori.de

350 euro for the fiberglass part
100 euro for the MRA screen

Inquiry sent, shall know soon if they're still manufacturing them.

Looking back through some unshared pictures, I also found some valve seat pictures for the 40mm Ti intake valves. The cut goes like this:
45 degree seat

That's it, no throat cut, no top cut, no backcut on vavles, just a straight 45 degree seat cut and called it a day. Looking at it, it's apparent the head was ported before seats were installed; there's not a single mark on the seats in the throat, they weren't ever worked. or shaped, just straight throat and the bowl is curved to meet the seat.

- So, for any 265 kit owners, there's your extra flow to be had if you know what you're doing with valve seats and valve back cuts.
- No de-shrouding was done either around the seat in the chamber, so there's some more gain.

A project for future me...
 
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I can say on a Lush head there must be 5 angles on intake and exhaust has some different stuff going on, I believe this is what a rocket head will look like to flow max. This is by hand also, the guides, the bowls, its just a masterpiece im very proud of and hope soon to have in action on something pretty special, pictures do not do show details very good
 

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I am not at all surprised to see the extra care taken on that Kevin.

I got a response from Millennium Technology regarding tappet boring.

In short: no, they won't/don't do it, but do have a Newen single point for seats and can top cut the guides for increased cam lift space.

Will be checking with a local shop that looks promising for a top to bottom machine shop solution. They do racing engines, boat engines, aircraft engines, and land speed engines. Including crank grinding, line honing, head services etc. Will inquire about the tappet repair while there. I'll be bringing my spare head with so they can see first hand what needs done.

And....that's my summer break. Last big things to get done will be trimming and dropping the replacement frame off for coating and picking up the donor bike from Idaho. Back to school on the 25th, and this quarter is going to be a busy 10 weeks.

Fall progress will depend on my available time.
 
Finally found the manufacturer of the screen I was using, this one:
20230811_224921.jpg

I bought it 2nd hand from a French Captain on ebay, but motoplast is smart enough to embed their business card on the inside of the fiberglass area and I had the foresight to take a picture before I painted it, finally found the picture.

motoplast-gregori.de

350 euro for the fiberglass part
100 euro for the MRA screen

Inquiry sent, shall know soon if they're still manufacturing them.

Looking back through some unshared pictures, I also found some valve seat pictures for the 40mm Ti intake valves. The cut goes like this:
45 degree seat

That's it, no throat cut, no top cut, no backcut on vavles, just a straight 45 degree seat cut and called it a day. Looking at it, it's apparent the head was ported before seats were installed; there's not a single mark on the seats in the throat, they weren't ever worked. or shaped, just straight throat and the bowl is curved to meet the seat.

- So, for any 265 kit owners, there's your extra flow to be had if you know what you're doing with valve seats and valve back cuts.
- No de-shrouding was done either around the seat in the chamber, so there's some more gain.

A project for future me...
So now you've found another way to increase air flow in and out of engine and remove valve weight, no other angles on seats means they never trimmed the seats, another place to make better flow and power. Just keeps getting better and better. Just have to remove the head to verify and capture some more power.
 
I am not at all surprised to see the extra care taken on that Kevin.

I got a response from Millennium Technology regarding tappet boring.

In short: no, they won't/don't do it, but do have a Newen single point for seats and can top cut the guides for increased cam lift space.

Will be checking with a local shop that looks promising for a top to bottom machine shop solution. They do racing engines, boat engines, aircraft engines, and land speed engines. Including crank grinding, line honing, head services etc. Will inquire about the tappet repair while there. I'll be bringing my spare head with so they can see first hand what needs done.

And....that's my summer break. Last big things to get done will be trimming and dropping the replacement frame off for coating and picking up the donor bike from Idaho. Back to school on the 25th, and this quarter is going to be a busy 10 weeks.

Fall progress will depend on my available time.
Congratulations on the education, proud of you.
 
I couldn't leave it alone...
Pulled my 55mm throttle bodies apart to evaluate what needs done for DBW actuator fitment.
20230913_131230.jpg 20230913_131222.jpg

On the cable end, there are already 2 pivot locations. One male, one eyelet, that can be easily adapted for connection to the DBW lever arm using a heim or rose joint.
20230913_131250.jpg

So, at this point I'll be ordering the DBW actuator soon so I can mock up a test mount, validate, and then have one jet cut from aluminum. I have concerns about the bolts that hold the TBs together bearing the force, they're only 8mm diameter.

If it works out, I'll pull the 58mm set apart and fit it all up. Primary TPS will be the stock unit, backup TPS will come from the actuator.

Frame got degrimed today and will chop it tomorrow to haul to powder coater.
 
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If my measurements are correct, this will be an extremely simple adaptation to mount the ATP actuator using a fairly light weight bracket.

The ATP actuator is 43.5mm thick. From red to yellow is 45mm, so a 2mm thick bracket will position the actuator and lever arm very nearly in in parallel. A .5mm thick brass washer will even it and serve as a bearing surface for the heim ball to avoid steel on steel.
20230913_131250.jpg
I may use a 2nd bracket to support the actuator motor that extends out and relieve the two 8mm bolts of the bending stress of a cantilevered motor.

Close tolerance slip on over teal lines and a 2 part clamp around orange will provide a strong support that will alleviate stress on the 8mm bolts. The silver rails are supported by collars in the TBs and not just the 8mm bolt.
54851d1c0aeed495cf434fe7a9ced6641975e0df.jpeg
20230913_152228.jpg
 
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It's not something I've found lacking at my power level. Once the walbro is tapped out, around 550hp, I'd start looking at a new rail that has a return line plus an adjustable FPR like Art is using on his bike.

An easy solution would be to use the existing port as the return outlet and weld a larger ID AN fitting to the opposite end as the input.
 
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