Victoria! Zeke's CB175 Build

[crazypj]

they are not parallel but the part numbers said they were compatible. At the bridge the fork tubes are slightly wider than at the triple.


Sent from my iPad using Tapatalk

I don't understand what your saying either?
Need a pic.
You don't mean top and bottom yokes do you?
There are two completely different types and they are not compatible

 

[Texasstar]

I don't understand what your saying either?
Need a pic.
You don't mean top and bottom yokes do you?
There are two completely different types and they are not compatible

We have both sets and there is a vast differences. Are there more than two for the 350/360 models?


Sent from my iPhone using Tapatalk

 

[crazypj]

At 9,000 your target rpm is unrealistically low, use 11,000 minimum, 12,500 would be better and modify pistons to reduce weight so lessen stress on big ends and rods.
You probably want to find or modify cam with 280~300 duration for high rpm motor, you don't need wide power band to pull out of 'low speed' corners
You are likely to have issues with needle bearings in big end due to the cage arrangement, it was cheaper to make for production runs but does allow the bearings to scuff.
I forget which bike uses compatible but better cage, maybe the YZ or RM range with silver plated cage plus individual bearings (instead of paired bearings)

 

[crazypj]

We have both sets and there is a vast differences. Are there more than two for the 350/360 models?


Sent from my iPhone using Tapatalk

I think so but it's only the instrument mounts that vary

 

[teazer]

At 9,000 your target rpm is unrealistically low, use 11,000 minimum, 12,500 would be better and modify pistons to reduce weight so lessen stress on big ends and rods.
You probably want to find or modify cam with 280~300 duration for high rpm motor, you don't need wide power band to pull out of 'low speed' corners
You are likely to have issues with needle bearings in big end due to the cage arrangement, it was cheaper to make for production runs but does allow the bearings to scuff.
I forget which bike uses compatible but better cage, maybe the YZ or RM range with silver plated cage plus individual bearings (instead of paired bearings)

Paired bearings do scuff and fail at elevated RPM which is why Race Kit big end bearings were single rollers on the CB72. If you have an alternate bearing I'd use them in our motors too. We have not had a failure with ours running up to 11,500 at Daytona and Road America, so I wouldn't worry about it too much. If a crank was apart for new rods, though, it would be a good time to swap in better cages. Just avoid Honda supplied rollers. They are way to sharp on the ends and cause the cages to crack at the corners of the slots. We used to have to hand stone all the rollers before building a race kit type crank.

Target RPM should be 14,000 with that short 41mm stroke but the 160-175-200 motor cannot go there with sloppy cam control and thick rings and Mother Teresa long skirts. 200 has the same thick rings as a CB77 and they flutter above about 9,500. That's why they are trying a set of super light pistons with thin rings and short skirts like - insert personal fantasy here .

For really high RPM you need to reduce pumping losses too and change to a 180 degree crank and a high rpm type cam profile. Unless the motor can reach very high RPM, any cam beyond the mildest will hurt power in the middle and will add nothing at the top end.

Get those long cam chain guides in and eliminate one of the issues.

On the forks it sounds like the center to center distance is different between the top and bottom fork crowns/yokes/triples.

 

[Texasstar]

Paired bearings do scuff and fail at elevated RPM which is why Race Kit big end bearings were single rollers on the CB72. If you have an alternate bearing I'd use them in our motors too. We have not had a failure with ours running up to 11,500 at Daytona and Road America, so I wouldn't worry about it too much. If a crank was apart for new rods, though, it would be a good time to swap in better cages. Just avoid Honda supplied rollers. They are way to sharp on the ends and cause the cages to crack at the corners of the slots. We used to have to hand stone all the rollers before building a race kit type crank.

Target RPM should be 14,000 with that short 41mm stroke but the 160-175-200 motor cannot go there with sloppy cam control and thick rings and Mother Teresa long skirts. 200 has the same thick rings as a CB77 and they flutter above about 9,500. That's why they are trying a set of super light pistons with thin rings and short skirts like - insert personal fantasy here .

For really high RPM you need to reduce pumping losses too and change to a 180 degree crank and a high rpm type cam profile. Unless the motor can reach very high RPM, any cam beyond the mildest will hurt power in the middle and will add nothing at the top end.

Get those long cam chain guides in and eliminate one of the issues.

On the forks it sounds like the center to center distance is different between the top and bottom fork crowns/yokes/triples.

we are pretty excited about these slipper pistons they are a 111g with the pin vs the stock 147

g pistons. As you know we have plans for the rephase and we appreciate being led down this path. Zeke is learning how to TIG weld and he has been asked to apply at Texas State Technical College in the fall. Then we can make our combustion chambers the way we would like to. This summer feels like a crash course on everything from fabrication to engine building. Cramming what we did in a year and a half into ten weeks is challenging while still maintaining a sense of balance. We are learning many new things that require discipline everyday. We are still having fun. We have all three heads ready for the flow bench. Mike Riddle should have the fourth head back to us with the bearing modifications next week. Right now it seems a good target rpm for the build is 11k with a 500rpm buffer. Our valve train will be significantly lighter, smoother, and cooler. Would like to make sure we break in the pistons, heat soak, and seat the rings before pushing the limits.

Then we have multiple heads and gaskets to play with our compression. We have a 200 head that is a candidate to be welded up for high compression and would help us in the cooling arena. Do we drill out the left side of the 200 head to feed the left cam ear?

 

[Texasstar]

At 9,000 your target rpm is unrealistically low, use 11,000 minimum, 12,500 would be better and modify pistons to reduce weight so lessen stress on big ends and rods.
You probably want to find or modify cam with 280~300 duration for high rpm motor, you don't need wide power band to pull out of 'low speed' corners
You are likely to have issues with needle bearings in big end due to the cage arrangement, it was cheaper to make for production runs but does allow the bearings to scuff.
I forget which bike uses compatible but better cage, maybe the YZ or RM range with silver plated cage plus individual bearings (instead of paired bearings)

Thanks Crazypj. We have plans for a hotter cam down the road. We picked up a capellini adjustable cam sprocket for our 175 cams. We have more cams to send off but they will have to wait. We plan on beefing up the lower end down the road so this is good info. Thank you.

 

[Texasstar]

http://youtu.be/j_1KKyR9MCA tunnel fab

 

[Texasstar]

The cr72 valve weight was 26.9g this is where we will be

Sent from my iPhone using Tapatalk

 

[Texasstar]

Replacing the 175 oil pump and plunger with the cb200 plunger and pump direct bolt up.
The 175 plunger is 13mm
The 200 plunger is 14mm

Sent from my iPhone using Tapatalk

 

[Texasstar]

Guess which clutch basket is lighter? The cb200 or cb175?


Sent from my iPhone using Tapatalk

 

[crazypj]

Do the oil transfer piece modification - same as on CB350/360. Upgrading the pump will cause problems at high rpm without higher flow from centrifugal filter
I would also check the possibility of fitting CB350 pump then run external oil feeds to cam bearings

 

[Texasstar]

Do the oil transfer piece modification - same as on CB350/360. Upgrading the pump will cause problems at high rpm without higher flow from centrifugal filter
I would also check the possibility of fitting CB350 pump then run external oil feeds to cam bearings

i looked up the oil transfer piece mod but it wasn't clear what they did. It looks like he ground down the back???? what is in involved with the oil transfer piece modification?

 

[Texasstar]

Never mind I found it lol http://www.dotheton.com/forum/index.php?topic=43545.0

 

[acm177]

You could take that basket down to a single gear drive to get it even lighter... I used the other gear as a guide to flatten the cushion holders with a hacksaw blade and file.

Then you'll have a spare when it wears out

 

[acm177]

Oh yeah-- Here is my pattern for additional speed holes...

If you want me to email you the cad file (.dxf wont upload) let me know your address...

 

[Texasstar]

Oh yeah-- Here is my pattern for additional speed holes...

If you want me to email you the cad file (.dxf wont upload) let me know your address...

you guys are the best!


Sent from my iPad using Tapatalk

 

[Texasstar]

You could take that basket down to a single gear drive to get it even lighter... I used the other gear as a guide to flatten the cushion holders with a hacksaw blade and file.

Then you'll have a spare when it wears out

!!!!!


Sent from my iPad using Tapatalk

 

[Texasstar]

Captain America got his windscreen for the NSU Sportmax Dustbin. Happy Independence Day!

Sent from my iPhone using Tapatalk

 

[Texasstar]

Trying to improve upon the bang. We used Taylor 8mm spiro core on lucky but I just found a guy who tested them and they have 300 ohms resistance. Looking at these http://www.amazon.com/MSD-Ignition-34039-8-5mm-Conductor/dp/B00062YYEU/ref=pd_sim_sbs_auto_1?ie=UTF8&refRID=1JFKCK1AJKZE5HPG1M4T

MSD Superconductor. What do y'all think? http://www.ls1.com/forums/f63/tested-all-major-spark-plug-wires-my-results-31657/

Also thinking about going to a 3ohm coil this time since we will be total loss ignition.


Sent from my iPad using Tapatalk