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Discussion Starter · #1 ·
i was thinking on putting turbo on my bike (yamaha xj400) but i was stucked at planning on how it was rigged into the carbs.

I'ved read about the blow through and draw through systems BUT....

i was worried on having too rich on lower RPMs and lean on Higher RPMs...

does anybody know a diagram or link or anything that will help me solve this??

PS.
i was also thinking on pressurizing the carbs to overcome this BUT is it right and how??
also im a bit newbie around bikes and i do most of the stuffs by myself (DIY)....

Thanks!!
 

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science bitch
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I would head over to amazon and pick up "Maximum Boost" by Corky Bell. Should have everything you would want to know, and it's really nice to be able to reference back to when your elbows deep in it.
 

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Hey there! I have that book it is a great book for info on everything turbochargers.no info on superchargers though. It is worth it! It has helped me with plenty of car projects.
 

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Lol yes it works for bikes its general info on turbos it will give you what you need. You will be able to adapt the info to bikes just need to do some math e.c.t
 

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UnicycleMode
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had a glance at the book a while ago. it was interesting.. it was for cars will it work to bike??


Pretty much comes down to a combustion engine is just that regardless of being in a bike or a car. The rich/lean worry you have, with enough knowledge, you would know that the pitot tube that pressures the float bowls of the carbs keeps fuel moving when boost begins building.


Supercharging isn't voodoo either, it just takes a healthy knowledge of what pully ratios your going to need so you can use the S/C unit in its effective range of rpm.



There is a great deal of threads here on CF dealing with exactly the stuff your asking about and on top of that it seems more and more there is threads popping up asking about exactly this subject. I think we need a basic turbo sticky thread that breaks down the required parts, the design stages of an intake manifold, and the theory behind why turbocharging is a suitable option.






3 key facts about turbocharging:


It is not cheap. You can't just slap one on a bike and go. That is, unless your paying thousands upon thousands of dollars to have a pre fabricated kit sent to you... even then it takes some knowledge of what your doing and there is still the tuning aspect of it if things are not just absolutely perfect.


The gain is mediocre at best with any engine that your developing a kit for as it stands. I've explored the option on alot of middleweight bikes and your going to end up with a 15-25hp gain in a safe state of tune. Most builders I've talked to don't think it's worth the cost of a second bike, just to squeeze 1/3 more power out of your standard 400 twin. That is up to you really.


And the last thing your going to need to know is that there is very little info out there on bikes like middlewight machines. Forced induction is a sliver of a big market aimed at beginner/standard/middleweight bikes. You might be better off finding a 600cc four to stuff into a 400 frame in order to make the exact same gain a 400 with a small snail would get you.






With that said, what is your goal? Just a little more power? Or are you trying to get it to wheelie up on the power in 4th gear? Might be able to suffice with just a set of flat slide carbs and a nice exhaust for a little more power, but may find a bigger engine swapped in would provide the big numbers if that is what your after.

Running total cost for all the turbo parts I've put together for my 400 twin thus far is just under $2,000 (usd) and I've yet to build a plenum, buy the mild jet kit for the carbs, or build any of the hard bits like exhaust manifold or the oiling system. I'll be in it to win it at about $3500... on a bike I got on trade for a non runner project. Your priorities may not line up with mine when it comes to what is worth the cost. ;)
 

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lɐʇuǝɯᴉɹǝdx&#4
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Like Rat Fighter said; unless you have a specific goal that requires forced induction, chances are a bigger engine with optimized intake / exhaust is the way to go. You end up adding lots of costs (and weight) besides just the raging snail cages. For the same weight and cost, bigger displacement generally gives better return on time and money spent.

I know its tempting to think you can take a bike you love (or at least already own) and add some cool turbo bits for "free horsepower". But that's pretty much the HARDEST way to build a fast bike that's fun to ride.

Source - was thinking the same thing as you 4 months ago, gave up before I even bought any books. Seems like its just not worth the hassle on a bike that doesn't have FI; most folks replace carbs with injectors when doing turbo if they don't already have them. I'd imagine some rare folks are comfortable enough re-jetting carbs, drilling jets, etc that they can make it work... but they are the sorts who ANSWER these questions, usually with "don't bother".

Look at it this way - getting a turbo to work right on ANY bike is probably gonna be a minimum of $2K, and that's an "ideal world" figure. Knowing that up front, wouldn't you rather buy a project bike, one with an engine that can hit the performance you want without resorting to forced induction? $2k can build you a pretty nice fighter if you put in the same labor would go into putting turbo on some bike never built for it. And then you have two nice bikes, not one that (most likely) has some very serious quirks (if it is even ridable). If you can do a turbo cheaper than I said, chances are you can do a whole bike equally cheap as well.
 

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lɐʇuǝɯᴉɹǝdx&#4
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Could anything be swapped over from the xj650 turbo?
The engine?

But yeah, having the whole system of a turbo Seca (say one with a seized engine) would be a huge shortcut. The carbs are actually designed to work right with a turbo. There may be a fuel pump involved as well. The airbox actually has a valve to let the carbs draw in air when the turbo isn't spun and would impede flow. Lots of stuff that would be a PITA do do yourself, and might not work well unless balanced properly.

Not sure how well it would work on a smaller engine, though. If anything, I'd want to try putting it on an xj750 or xj900. Seems like the 400 is unlikely to ever see full boost, since it would only provide ~60% of the hot gas to the spool you get from the 650. With the bigger engines, on the other hand, full boost would hit at lower RPM...
 

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Discussion Starter · #13 ·
moving to a bigger displacement bike is a great idea. but bikes in here(Philippines) are way too expensive.

a 650cc bike would cost me around $6k. so i resorted to turbo-ing the system, also I also want to learn more about the world of turbo...

thanks a lot guy for those brilliant inputs!!
 

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moving to a bigger displacement bike is a great idea. but bikes in here(Philippines) are way too expensive.

a 650cc bike would cost me around $6k. so i resorted to turbo-ing the system, also I also want to learn more about the world of turbo...

thanks a lot guy for those brilliant inputs!!
a Friend of mine imports bikes from florida to the Philippines he says he is killing it
 

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UnicycleMode
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moving to a bigger displacement bike is a great idea. but bikes in here(Philippines) are way too expensive.

a 650cc bike would cost me around $6k. so i resorted to turbo-ing the system, also I also want to learn more about the world of turbo...

thanks a lot guy for those brilliant inputs!!


If your really that determined on turbocharging this site has a bunch of affordable parts for such a venture. ;)


Bought my IHI turbo from them. Solid company to deal with and the parts they offer are generally adapted from turbo car type applications. The big injector they offer for the 400-800cc EFI kit is directly pulled from a Dodge Neon. Just as an example of the readily available parts they offer in the kits they sell.

http://www.ecotrons.com/
 

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lɐʇuǝɯᴉɹǝdx&#4
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If your really that determined on turbocharging this site has a bunch of affordable parts for such a venture. ;)

Bought my IHI turbo from them. Solid company to deal with and the parts they offer are generally adapted from turbo car type applications. The big injector they offer for the 400-800cc EFI kit is directly pulled from a Dodge Neon. Just as an example of the readily available parts they offer in the kits they sell.

http://www.ecotrons.com/
Damn you for restoring my dreams. Seriously, they look like an amazing resource. The system prices are very good, and look to have a LOT of features that would be useful even without a turbo project. For example, the data logging ability would make it possible to "dyno tune" without a dyno, under real world conditions, letting you test the effects of different airbox / air ram designs.

Maybe in a year or two.
 

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UnicycleMode
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Damn you for restoring my dreams. Seriously, they look like an amazing resource. The system prices are very good, and look to have a LOT of features that would be useful even without a turbo project. For example, the data logging ability would make it possible to "dyno tune" without a dyno, under real world conditions, letting you test the effects of different airbox / air ram designs.

Maybe in a year or two.









It's kind of interesting how I run across companies like that too. I wouldn't say I'm a guru of any sort when it comes to turbocharging or even outright building motorcycles. There is plenty I don't know, but I am always trying something new, going a different direction, finding what works and what doesn't... but without a budget that would reflect my ventures in motorcycling... barter, trade, and often times just free parts leads me into being able to fill in the gaps with stuff from companies like ecotrons. ;)

Most around CF, and in my personal life, know me as the "old iron type of guy". If it ain't got air cooling and iron sleeves I'm pretty much not too interested. Turbocharging is always on my mind though, the principal and the operation is so simple that it's painful to hear people over complicate it stating numbers usually related to only one or two experiences or situations.



So here is something that was brought to my attention by a guy here on CF that turbocharged his Suzuki GS. The charging system! What kind of amps does it put out? A fuel pump can draw alot of power, then add in a scavenge pump and some lighting, turn on a blinker and hold the brake, your drawing much more than you think. If your fuel pump can't keep up, or your scavenge pump slows to a crawl, it can mean your spending even more money on a stator setup that can make things function properly. There are so many variables to a build that involves adding parts to the bikes functioning systems that it's hard to grasp just how much thought and planning it will take to put it all together properly.

My most current of turbo bike ventures is a Bandit 1200, soon to be utilizing a ProBoost kit from Finland (if it's available, why not?), then I have a GS500E I'm working out the hard parts for so I can run a blow through system on it... may eventually end up with EFI if the carbs just won't hold up to the pressure. And to top that off my brother and I have been in contact with a shop that has built numerous turbo bikes and have been discussing the finer points of how to go about developing a daily rideable turbo setup for the 2011-2012 CBR250R. All of the above bikes will end up, by the end of it, with about 3k into the turbo parts and associated fabrication work to get things going enough to strap it to a dyno. That isn't adding in the data logging equipment, or parts that will wear down during testing, like tires and chains.





Turbocharging is like a trophy wife, she doesn't love you the way you love her. And all the romanticizing you can do will only let you down harder when she spits in your face and takes you for every penny you have. ;)
 

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lɐʇuǝɯᴉɹǝdx&#4
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So here is something that was brought to my attention by a guy here on CF that turbocharged his Suzuki GS. The charging system! What kind of amps does it put out?
XJ bikes (at least the 650 and 750 models my Haynes manual covers) have abnormally strong alternators (19A @5000rpm) for the era. Would probably want a better rectifier, and certainly a better fuse setup. I've already put in a stronger battery (more CC amps and capacity both) and will be going through the harness to improve the connections.

My lighting will eventually be ~100 watts worth of LEDS (all up with brakes and signals) but I guess that's potentially 9 amps right there... ugh. Yeah, I see your point....
 

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UnicycleMode
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gsryder brought that to my attention a few months ago and it pretty much blew all chances of my CB360 ever doing more than powering its own ignition... so down the road that project went. :(



Thing I keep thinking about is how to mount a small belt driven alternator for the demands of the system. Same way an oil pump on a drag bike is driven, hell, you could do away with the stator all together and run a weighted and balanced pulley off the crank like a car. :D


Bikes that come to mind with decent output alternators are gold wings, and air/oil suzuki's. Some machine work to adapt a pully for a belt drive to it, to replace the gear drive it has standard, I think would suffice to transmit crank shaft to charging system. But at that rate most people would just swap in a bigger engine and be done with it. Talk about over complicating what seems at the beginning to be a simple project.
 

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lɐʇuǝɯᴉɹǝdx&#4
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On the same topic of over-priced engine mods... N2O. I just had the crazy notion of pulling the end plugs off my YICS tubes and screwing in feeds for N20.

For those not familiar with the YICS system (used on most XJ bikes and some others) it is a miniature merged intake sub-tract that lets small amounts of mix cross at high velocity between intake tracts, then join in to create a nice big swirl in the combustion chamber. You actually need to plug it up (with a correctly sized rod) to be able to sync the carbs, and do so simply by removing a bolt that screws into each end of the YICS track and sticking a snug fitting rod with some expandable rubber fitting (called a "YICS tool") clean through from one side of the head to the other to block off the cross feeding.

Seems like its just ASKING for somebody to set up injectors in the bolt holes the plug the ends of the track, and spray N20 in there. Guess it would be a dry system, which has its own problems, but I don't think you can do wet without a fuel pump, nor is the YICS suited for delivering the required volume of fuel.
 
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