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Discussion Starter #1 (Edited)
Dad inspired Honda CL350 on the journey to Bonneville

So my dad bought a honda cl350 new in early 1971 brand new..Not long after he got rid of it due to enlistment in to the navy.
Many many years later I as an adult now hearing stories of his old bike and my already life long ride on two wheels lead me to have the feeling of "I have to have one"..which after months of searching for a suitable project I stumbled upon this 1971 cl350..
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after getting the ball rolling I was able to locate a cl tank in the same color of my dads bike and things got to this point.
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with some more love and some tinkering and a few new parts I have mad it to this point.
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I will be updating and adding specs soon..I have alot more parts coming and plan to get this ol girl to bonneville for speedweek next year to contest the 350cc p,p class.
 

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I don't think it qualifies for production, either. SCTA says it must "appear identical in all respects to the production model it represents".

Chris
 

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yeah, kinda on the wrong track and heading backwards...
 

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P/P is Production engine/production frame. The paint won't disqualify it from Production class but the bars and no muffler will. And the seat will too. Must run stock seat and fenders. The way it stands will move it into Modified. And the unfortunate thing about that is they used to let TZ350 Yams in that class so it is pretty much a screwed up class. You could always hook a sidecar platform to it and run sidecar class. The record is 121 and held by a CB 350. There is also the all bike BUB meet at Bonneville. But what ever please bring it out. You won't regret the experience of riding on the salt. But do get a rule book. You will need one. The days of Burt Munro are long gone. You need a rule book.

I'm heading out to SpeedWeek next Thursday. Hope to arrive Friday. Get through tech Sat. and go racing.


P.S. If you need a reason to go here is the best view in the world. Especially if you are aiming something at it.

 

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Discussion Starter #6 (Edited)
P/P is Production engine/production frame. The paint won't disqualify it from Production class but the bars and no muffler will. And the seat will too. Must run stock seat and fenders. The way it stands will move it into Modified. And the unfortunate thing about that is they used to let TZ350 Yams in that class so it is pretty much a screwed up class. You could always hook a sidecar platform to it and run sidecar class. The record is 121 and held by a CB 350. There is also the all bike BUB meet at Bonneville. But what ever please bring it out. You won't regret the experience of riding on the salt. But do get a rule book. You will need one. The days of Burt Munro are long gone. You need a rule book.

I'm heading out to SpeedWeek next Thursday. Hope to arrive Friday. Get through tech Sat. and go racing.

P.S. If you need a reason to go here is the best view in the world. Especially if you are aiming something at it.
Thanks for the points in the right direction,2013 Rulebook has been ordered! Guess that's what I get for baseing things off word of a friend..lol..Oh well..I am gonna run in what it fits in when done..Mainly doing this for the ride! Setting a record is not the first priority at all.The BUB event sounds really cool with all bikes..Might try for that one,be a lot more chill than speedweek im sure..Which on that note,Good Luck and have fun!!..Ps Did you know your legs are pointing the wrong way?? LOL...Looks like street ludge gone wild..j/k
 

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Discussion Starter #7 (Edited)
Ok so after much picking of Hoofhearted's brain and the getting of a rule book,I have got myself going in the right direction towards a class more suited towards my style bike.I am gonna be running in 350cc modified/blown gas.
So then I ran into the obvious problem being my bike is not blown.But with a quick look around around I snagged up a rhb31 turbo for the low low with a set of flange plates that I should have early next week,quick trip by my buddy's house that runs a turbo busa netted me a free blow off valve,some silicone hose,oil lines and two aluminum weld on bungs for plumbing the case to oil the turbo.So being all pumped on my parts spree today I came home and got working on a manifold.I am gonna stand the turbo up so the air filter is facing straight up,it gonna be positioned right in the front under the right side of the tank,I wanted to keep it in the front of the bike for cooling.So after a few cuts and some fiddling I came up with this for my manifold,I gotta finish weld everything up yet and I am gonna flare out a 2" pipe to weld on to single it down and add a 90 into the turbo.
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Wait till you find out the cb350 doesn't pump enough oil to properly oil the turbo. Then the real fun begins.
 

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Slow down grasshopper - You better give this turbo option a little more thinking before you start fabrication. To start with you will have an oil issue as Geeto has pointed out. You have basically two ways of connecting a turbo to you bike - it can be setup much like your buddy's bike and have the turbo blowing into the inlet of the carbs. If you use this method, you will have two carbs that have to be pressurized and two carbs that have to be jetted with the turbo. Plus you have to build the inlet to the carbs and deal with what ever room you will have between the engine and frame. This setup in my opinion is the most complicated way of installing a turbo.

The other method you can use is to have a single carb connected to the turbo and have turbo blow directly into the engine intake. This is method was commonly used in the 70's for connecting turbo's to honda's and kaw's. You will need to add a fuel pump to the carb and build the intake for the bike. Usually the turbo will fit behind the engine and the carb is mounted to the right side of the engine. You still need to address the oil pressure problem, waste gate and tubing for the exhaust. I'd do a google on turbo setups and get a good plan in place before you start fabrication.

I'm thinking you might find some Youtube for turbo 350 hondas - good luck.
 

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there was a guy here who turboed a 350. look in the projects section. He managed to get it to work, but he kind of fell off after that.

FWIW here are the lessons I learned from my failed 450 turbo project:
- turbos need oil. the cb350 makes like 15 psi of oil pressue at redline, most turbos need 40. so check your turbo oil requirement. Be cognizant of volume and pressure, 40 psi at half the required volume is still a recipe for failure. Some of those small speed snails can spin in excess of 30,000 rpms - oil is the life blood. Also Turbos get hot, It is afterall driven by hot exhaust gas made hotter by forced induction. Oil is the cooling fluid for an air cooled engine so if you are passing your oil through a very hot turbo then you robbing it of its cooling properties for the engine. You WILL need an oil cooler, a big one. And probably a bypass for warm up or that engine will take forever to get hot.

- For what you are doing a draw through is the best setup. Well actually FI is the best setup but I doubt you have the time or the budget for that. A draw through will allow you to make easy carb changes to accomidate changing atmospheric conditions. Think hard about your carb choice - DO NOT USE A CV CARB. This means you can throw away the stock carbs they are useless to you. I recommend an S&S Super E - why? well for starters you can get parts at every Harley dealer from here to the moon so it is hard to be caught short. If you think this is too great an expenditure try and get a Mukuni VM carb and a decent set of jets. Commonly available parts from sudco, and larger sizes should be easy to find - they were an "upgrade" for old Ironhead sportsters over the stock carb. Not sure of the size but that is something you need to figure out based on your turbo specs. I will say it is harder to "over carb" a turbo engine because the waste gate regulates how much is going into the engine. Carb placement is critical - you don't want the fuel line passing over anything really hot (like the headers or the top of the engine) because radiant heat transfer will cause the fuel to boil in the line and you will get vapor lock (I deal with this every day on my I-6 jeep because I installed headers and now the heat passes right to the fuel rail - it's no fun).

- Turbo placement. Too long a down (exhasut) pipe and it takes longer for the turbo to spool. Too long a charge (intake) pipe and there is potential for bleed off. In your case I would favor a shorter down pipe and use a slightly bigger turbo - you can feed lots of volume at low pressure and give the engine a fighting chance and make more power but you will use every inch of those 4 miles to get there. The more pressure you have the more problems you are going to have, so you might as well opt for more volume and deal with the horrible lag.

- charging system. you are going to need a fuel pump, to feed the carb. the cb350 charging system can't support this in a street application but it might in a racing application. Also one of the dark paths you might go down is a seperate oil system for the turbo from the engine oil. If you do this - the old 70's turbo drag racers used to use AeroQuip fuel pumps to drive oil to the turbos on HVLP oil pressure bikes like the suzuki GS and the kz1000. This draws a lot of current. the stock charging system probably won't be up to the task of powering this and the fuel pump. If you are considering this, then I would probably find a way to run the engine off a magneto, and use the charging system to power all sorts of pumps. A big battery won't hurt either.

- Remember you are building a race bike. Forget the street shit - you can always add that back in later. Focus on getting it within the confines of the rules and parameters for the run. Remember it only has to run at WFO for a couple of minutes and do it two times, so it is ok if you have things that have short life spans, just remember to pack a lot of spares for those things (there are very few turbo impeller bearings out on the salt).

- Don't worry about weight creep. the bike will get heavier. All out land speed doesn't feel as much of the weight penalty as acceleration does. I mean you don't want an 800lb motorcycle but if you add 100 lbs over stock don't stress about it. I have heard from several reputable sources that some bikes need weight ballast just to be able to run on the salt.
 

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one last thing - I know you think it is all cool and stuff that you painted your engine black (poorly I might add, I can already see it chipping in your pics) but that is lousy for heat transfer. you may want to strip that crap off your barrels and head so you can get some more efficient air cooling back in there. Remember: Forced induction = heat.
 

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Looks like you'll need a 2014 rule book now as Speedweek starts tomorrow. I couldn't make it but Bob is out these with the Metro going for 300mph. I'm guessing he'll do maybe 272.mph. Our current record is 265. Made some changes that should net some good gains.
 

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they do the updates on the website for the rule book, so if he has a 2013 rulebook he can download the 2014 amendments when they come out.
 

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Either way I am glad the OP is looking at it realistically and looking to just make runs and not intending to break the record. That's an awfully hard goal to accomplish.
 

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Either way I am glad the OP is looking at it realistically and looking to just make runs and not intending to break the record. That's an awfully hard goal to accomplish.

P/P is not pushrod class, but production frame/ production motor. That record was set 18 years ago on a Yamaha @128.537mph. Surprisingly the M/BG class (modified frame/blown gas) class record was set by a Honda 5 years ago at only 74.935mph.
 

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Discussion Starter #16 (Edited)
Well all of the mentioned issues were really already addressed before I even got started....

Oiling issues with the turbo can be resolved by simply keeping the turbo below the oil feed line in the engine,or if that doesnt remedy it I can add an oil cooler or a fuel filter that you can remove the element from in the feed line(which im gonna do anyways)to basically add a reservoir in the line so the turbo wont dry out due to low pressure.all else fails I have an electric oil pump..

Fuel issues can be handled in several ways,one is efi..which is the route I really wanna go but I am pretty sure that would bump me out of modified/blown gas and into modified/blown injected gas?
if it dont,im gonna go efi...if it does im gonna use stock rejetted carbs and use a large fuel filter in each feed line to combat having to have a fuel pump..Im only looking at running 5psi boost at most so fuel starvation shouldnt be an issue with an oversize filter basically reservoiring the fuel line according to my my buddy thats been running turbo bikes for around 15 years.

the electrical system sucks plain and simple,so im gonna try as many options as I can to keep from adding current drawing devices,i dont even know if it can even keep up enough to manage a efi system..I am looking in to getting my stator rewound,got a old guy local that says he can bump my system to something real close to 150w by rewinding my stator which is a ton better than 100..but we will see what happens..I have roughly a year of trial and error to get my stuff together.

and I love my black cheap o paint,and its not chipping,it has been sanded off in spots..but i was smart enough to get a paint with a rapid heat echange rate.

The modified/blown gas class record is at 100.294mph i do believe,which really truely is an obtainable goal for my bike.If I get a record awesome,if I dont no big deal..Im going to have fun and see how fast I can go! but it is always good to have certain personal goals to fuel motivation.
 

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I was looking at a 2011 book so the record has been upped since then. Keep in mind that these records are usually set by hardcore racers and engine builders. If you don't have experience with this you may find you've bitten off more than you can chew and will spend a lot of money sorting out a fast bike that may not reach a record that pays nothing more than bragging rights. Don't get me wrong, it can be done. I did it with a car in 2011 having built from scratch in 2-1/2 months a 59 Nash Metropolitan that broke a 14 year old record at over 262mph. Something that everyone who saw the car when we showed up at B'ville sadi that what we expected was impossible, we left a lot of deep pocket engineers scratching their heads after breaking the record that week and resetting it everytime we've been back and will break it again this week. Hooffarted I believe also has a record. I am preparing my XR1327 for an LSR run (if I ever get my motor back) and know what big shoes it takes to set a record. Keep in mind a record is something no one else on earth has ever done, and many have tried with big crews and deep pockets. Good luck with your project.

I don't believe there are any restrictions on carburetion or injection once you get into modified, It just can't be bigger than 350cc +.5mm (.020")
 

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Discussion Starter #18
I know what it takes to go after records realistically..I am mainly focused on getting there and having fun hangin with all the speed junkies soaking in the scene.I do however want to hopefully make some consistent runs and then if all is well and the stars and moon aligns,make a go at the record.I am confident in my skills as a rider and fabricator,we just gotta see how this bike plays out over time I guess..lol.Might die before I get there.But hey,Im up for the challenge.
 

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I just acquired a 1972 cl350 and am undertaking moderate restoration i.e. want it to run excellent and sound and look very good. Want to cut the muffler off and leave the pipes as shown in your photo. Did you leave them that way, insert baffles or add shorties? Did any of this require re-jetting or other modifications?

Would enjoy seeing a photo of the completed project.
 
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