VW trike hydraulic clutch problems

[Zar]

Here is what it looks like at the moment, I will be using the hood from a 1949 Chevy, so there will be a lot of space for air to flow,---

I know it's on the back of the trike...but it covers the engine... so it's a hood . Right? - I'll call it that-

So the hood will come right to the saddle, so behind the passenger spot- there will be a pebble guard, from the hood to the deck. this will allow air to flow pass the heads and the whole engine... I will also have a pebble guard under the engine, so basically making an engine compartment that allows plenty of air flow.

was also considering making a sort of shroud to channel the incoming air stream...

 

[Gone2Three]

Hey Zar, that's going to be one sweet machine. Thanks for sharing your pictures with us :clapping:

 

[DeathBySnuSnu]

72 to 74 1700cc

Can not tell if originally in vw or porsche.

Tins

https://www.thesamba.com/vw/classifieds/detail.php?id=2166224

 

[DeathBySnuSnu]

Ducted air flow can work. It is harder to do in the back.

Type 4 has a lot more fin area and can shed heat better than type 1.

The big drawback of ducted air is that you have to be moving for it to work. No city traffic, no parades, no stop lights......ect. Then you have trouble pulling a heavy load like a trailer. Normally you are so lightly load that you dont have have a lot of btu to shed. But demand more load means more btu to get rid of.

I would suggest finding the tins for your rear engine set up.

 

[sdewolfe]

hydraulics

I have lurked here for a long time but I have not been active in several years. I got an email encouraging me to participate. When I saw this post I just had to comment. Brake and clutch systems are really important to a safe and fun to ride trike.

I looked at your drawing. The pedal lengths you measured are 4.25 pedal to pivot and 2.75 pivot to master cylinder rod. These two values are not additive, it is a ratio; 4.25/2.75 = 1.5:1

Assuming one square inch of master and slave areas to simplify, on a 600 lb. clutch you would have to generate 600/1.5. = 400 lbs foot pressure. It needs to be about 1/10 of that. It looks like you have the same ratio on your brakes? That will require even more pressure. Maximum braking requires something like 1500 lbs. line pressure; 1500/1.5 = 1000 lbs. foot pressure with your current lever ratio. 1500 lbs. of line pressure is not a hard and fast number, you will have to do some calculations to determine actual required line pressure. But it will do for an example. I read once, somewhere many moons ago, that maximum foot pressure during a panic stop should not exceed 120 lbs.

Remember that as the ratio goes up (let's assume 7:1 is what you settle on), travel at the master cylinder rod decreases. that is to say, 7 inches of pedal travel will equal 1 inch of rod travel. Don't forget that the master cylinder diameter and the slave cylinder diameter also form a ratio that has to be calculated to know the line pressure required.

I recommend that you get a copy of Fred Puhn's "Brake Handbook", read it cover to cover. Then get a pressure gauge that screws into the bleeder ports to first, verify current pressure you can generate with your foot and then, to verify that your improved system design matches the math you use to design it.

I just read what I wrote and I am hesitant to post it now. I come across as a know-it-all. That is not my intent. I don't know nearly enough. I am just trying to help you design safe and ergonomic hydraulic systems for your trike. I hope I have been helpful.

 

[rhino 2]

I have lurked here for a long time but I have not been active in several years. I got an email encouraging me to participate. When I saw this post I just had to comment. Brake and clutch systems are really important to a safe and fun to ride trike.

I looked at your drawing. The pedal lengths you measured are 4.25 pedal to pivot and 2.75 pivot to master cylinder rod. These two values are not additive, it is a ratio; 4.25/2.75 = 1.5:1

Assuming one square inch of master and slave areas to simplify, on a 600 lb. clutch you would have to generate 600/1.5. = 400 lbs foot pressure. It needs to be about 1/10 of that. It looks like you have the same ratio on your brakes? That will require even more pressure. Maximum braking requires something like 1500 lbs. line pressure; 1500/1.5 = 1000 lbs. foot pressure with your current lever ratio. 1500 lbs. of line pressure is not a hard and fast number, you will have to do some calculations to determine actual required line pressure. But it will do for an example. I read once, somewhere many moons ago, that maximum foot pressure during a panic stop should not exceed 120 lbs.

Remember that as the ratio goes up (let's assume 7:1 is what you settle on), travel at the master cylinder rod decreases. that is to say, 7 inches of pedal travel will equal 1 inch of rod travel. Don't forget that the master cylinder diameter and the slave cylinder diameter also form a ratio that has to be calculated to know the line pressure required.

I recommend that you get a copy of Fred Puhn's "Brake Handbook", read it cover to cover. Then get a pressure gauge that screws into the bleeder ports to first, verify current pressure you can generate with your foot and then, to verify that your improved system design matches the math you use to design it.

I just read what I wrote and I am hesitant to post it now. I come across as a know-it-all. That is not my intent. I don't know nearly enough. I am just trying to help you design safe and ergonomic hydraulic systems for your trike. I hope I have been helpful.

Great post ......All information is good.....Don't ever hesitate to share. that is what's great about Trike-Talk .......Nobody shames anyone....ThumbUp

 

[DeathBySnuSnu]

I come across as a know-it-all.

I probably have that title locked in solid.........

And yes this is what I was saying a couple pages ago.

7 to 1 is somewhere near the original vw pedals and the pedal only ratio, does not include any of the other mechanical or hydraulic ratios.

 

[LarryA]

LOL... most of what I have learned came from "know it alls".....keep on talking!!!

 

[grandpanystrom61]

I am still learning, keep the new info flowing as more answers to my questions seem to get answered.

It is a good morning and we all will have a good day.:clapping:

 

[Zar]

Awesome! thank you all for the info. I am in the process of re-building my pedals, I added a lot of length ( about 14"), hope that it will be sufficient, and I'm much happier with their over all mechanics ... i will get a copy of Fred Puhn's "Brake Handbook" ( it's in my ebay shopping cart), and if at the end of the day, I need to undo the whole pedal system and place the masters in a different location, I will...

I can't tell you all how awesome it feels to find other people that like building cool stuff, like trikes, who are kind and generous with the knowledge they have.:clapping:

 

[Zar]

Hey guys, thank you very much for all the help!

I finally got to do more work on the pedals... made them much longer, and of course, it took much more work than I anticipated. I decided to use much of the original parts and also some awesome scrap metal I found in the woods a few years ago. as soon as I got the pedals roughly done, I started it up and try the clutch... and bum! it worked ! I was able to get it in to gear with amazing ease, and so did the brakes. I could not get it in to reverse... but I need to finish the pedals, and make foot rests, because the pedals are much higher then before.

here are some pictures of the new pedals:

 

[DeathBySnuSnu]

Cool beans.

So now we are ready to see some more pics of the whole thing.

Also pics of some more of your stylized fabricating would be cool too.

 

[Zar]

Yes, I will take some photos as I finish the pedals... and as soon as I take it for the first ride, I will take some good clear pics to show you the almost finish trike... I do have a couple of weeks of doing my job hardcore- so it may be a month before I get there, but I feel much more optimistic now! again- Thank you for all your help.

 

[grandpanystrom61]

I hear that, but please do post pics when you feel like it. The work you are doing is interesting and how you did is awesome.

Not right now, but the desire to see about a hydraulic clutch interest me, but first I need to finish things up and get back on the road.

 

[Zar]

Got some more work done on y pedal, so here are some pics of the process... and I should be done with this job this Monday, so I will post more pictures then. I also ended up moving the battery box, so that it would not get in the way of the air flow to the right head. I looked at the tins that add for the tins that Rex recommended, and he does have the tins, but I can't afford it... he wants $650 - so I'm gonna use some cooling fans... but that will be ones I get the other stuff done.

 

[Zar]

Hello trike folk, here I am again... after I got the pedals all done, I started to look in to the cooling system, and took a look at the add that Rex / deathbysnusnu -posted here for me, and the gentleman did have all the tins I need, but he is asking $600 for it, and I can't do that at the moment, so I decided to design a cooling system that would hold me over until I can spend the money on tins or an aftermarket Porsche cooling shroud, and as part of this new cooling system, I used a 1949 Chevy sedan hood, that I altered, so it would fit and house a nice fan. for now I think i will use a regular switch to turn the fans on when I'm not moving... If there is a way to get a temperature sensor or a thermostat that you guys know about, to activate the fans, I will do that, but for now I will be the thermostat.

 

[Zar]

this is how it looks under the hood, the fan points straight down in to the block.

 

[LarryA]

really like your trunk lid!....curious, what's the blocky looking things on your rear bumper?

 

[Zar]

really like your trunk lid!....curious, what's the blocky looking things on your rear bumper?

Thanks. That is a piece of an old ATV tire

 

[Zar]

I do have a couple of questions for you guys... do you think that with this fans, I will need a more powerful alternator? the only one that I could find was a Porsche 914 alternator-

http://www.autoatlanta.com/Porsche-914-Alternator-Upgrade-srch.html



would I be able to use this in my 72... I saw a mention of a 120 amp alternator, but I can only find them for later models.

Also, should I get a pulley without a fan, to replace the one in my shroud... I'm thinking that the existing fan is not really doing anything other than create some resistance, and when people do those Upright fan conversions, the fan pulley is replaced with just a pulley. I also saw a conversion to a GM alternator that didn't look to hard to do.