Project CB350F cafe brat

stubsryan

Been Around the Block
Air leaks do cause high idle speeds on fuel injected engines as the injector compensates to keep the lambarda sensor in the right range.

Air leaks after a carb will mean that cylinder will be sucking less air and fuel from the carby because some of the air is bypassing the carb.

Also fuel only cools an engine after the maximum saturation point of fuel and air for that cylinder because beforehand it will combust. That’s not applicable in this situation because no one wants an engine running like that in the first place. Alternatively if you sprayed a small amount of water in with the fuel you can get some efficiency gains through cooling, otherwise it’s a mute argument.

Slides are working just fine. I’ve balanced the cylinders to an acceptable range.

Some of the things you are saying doesn’t make sense. I’ll sort it out and if you are right I’ll give you a shout out. We will see soon enough


Sent from my iPhone using DO THE TON
 

teazer

Over 1,000 Posts
DTT BOTM WINNER
G'day mate. It's your bike and you know what's best, so why don't we leave you to it.
 

stubsryan

Been Around the Block
IMG_2194.JPG


Sandblasted the side cover. Was thinking of trying to match in with the aluminium rear set. Not 100% convinced it will suit just yet but I can always paint it black later.


Sent from my iPhone using DO THE TON
 

Jimbonaut

Over 1,000 Posts
DTT SUPPORTER
Any chance you can bead blast that side cover instead? I dig the look and think you'd get it closer to the rear set too in terms of sheen. Still, not sure what bead blasting after sand blasting looks like, one way to find out...
 

stubsryan

Been Around the Block
Interesting idea. I might get some glass bead rather than the grit I’m already using and see how it goes. If all else fails I’ll paint it black anyway so it’s a safe bet to try. Also thought of maybe blasting the rearsets to match. I’ve got two complete sets so if it goes south I can always use the spare set but I doubt it will look bad. If anything it will look better with both the cover and rearsets having the same matte sheen. Cheers for the idea


Sent from my iPhone using DO THE TON
 

Jimbonaut

Over 1,000 Posts
DTT SUPPORTER
For sure mate, no worries - I bead blasted a bunch of engine covers and parts for the bike I'm working on and they came out really nice. I'll see if I can dig out a photo before they got painted
 

stubsryan

Been Around the Block
IMG_2265.JPG
IMG_2267.JPG


Deciding on final locations for the battery, fuse box and starter relay. Was going to buy a cool kit online but this way is cheaper and just as good. Decided to run a Lipo 4s 3ah battery because of its high c rating which will easily handle the start current of the starter motor.
Everything fits under the seat with a touch of room to spare. 5-10mm maybe. Also think I might do a cafe bump later because of the seating position. The rear support will help when I’m doing the ton out on the salt lake, Burt Munro style


Sent from my iPhone using DO THE TON
 

teazer

Over 1,000 Posts
DTT BOTM WINNER
Turnigy make great batteries but they are a touch on the touchy side when it comes to charging and balancing the cells. Do you have a charging system design that will work on this bike? I use a 1.3 4S on a drag bike, but it's total loss and I take a spare and special (but cheap) charger along to the strip.

SaVor on this forum, uses one on one of his bikes, but I don't know how he charges his to prevent overcharge or undercharge which can both lead to explosive results. Maybe a MOSFET R/R would do the job.
 

stubsryan

Been Around the Block
You can’t overcharge this battery with a properly functioning voltage regulator/rectifier. Also much like all batteries, you will stuff them up if you fully drain them


Sent from my iPhone using DO THE TON
 

irk miller

You've been mostly-dead all day.
DTT BOTM WINNER
It's not just a matter of whether your reg/rec is properly functioning or not. Different types of reg/recs produce different maximum charges. Plus, charge rate and discharge rate are more major factors that determine whether your system is a good match for your battery, especially with lithium batteries.
 

stubsryan

Been Around the Block
I’ve worked it out. It’s fine. A 4s lipo has a maximum charge of 16.8 volts. I’ve never even seen a voltage regulator that produces higher voltage than 16.8. Most are 14.7 volts. So in that case it’s impossible to over charge it. It’s actually annoying because I lose some capacity buy not being able to fully charge the cells but a 3s system isn’t enough. The 4s setup would be what’s inside the antigravity batteries. Interestingly, when you google antigravity battery tear down , there are lots of notices on the google page saying pages have been removed due to intellectual property infringement court orders. If it’s not Lipo it’s really high quality L-ion but that is unlikely because of the low c ratings.

Charge and discharge rate is why I chose the lipo chemistry because it’s high c rating. Basically you times C by AH and this gives you the maximum discharge rate. It’s way over 70a so I’m fine.

I’m an electrician and read a lot so that’s how I know




Sent from my iPhone using DO THE TON
 

teazer

Over 1,000 Posts
DTT BOTM WINNER
Bike batteries use different chemistry than RC batteries, and their individual cell voltages are lower.

One of many threads about Lithium batteries: http://forums.sohc4.net/index.php?topic=159364.0 That was Antigravity which is closer to 12v and presumably less tolerant of high charge voltages.

Those are LiFePo cells and 4S at 3.3v gives closer to 12v than a 4S LiPo RC battery at 3.7volts per cell - as I understand it.

There are some great youtube videos on LiPo type battery fires. I love the impact generated fires though. Quite spectacular. Complete head bangers generating a lot of the content, but that's Darwin at work. Lots of Ducati LiPo horror stories over on Ducati.ms

But to your point, they can and do catch fire on bikes that had been functioning quite well up to that point. As long as the voltage is monitored and battery protected, it should work.
 

stubsryan

Been Around the Block
Lifepo4 are good for 12 volt systems but their bulky size did not suit my application. Maybe antigravity are lifepo4 but I could not find any appropriately rated cells to build a battery. The charge rate for lifepo4 is so much lower than the discharge rate which is a small concern. I may use a BMS with a low voltage cutout and to balance charge the lipo so there is no chance of one cell over charging. I still haven’t decided about that though.


Sent from my iPhone using DO THE TON
 

DTT Bike Of The Month Gallery

DTT Light or Dark

www.jadusmotorcycleparts.com
shop.themotoworks.com
www.cognitomoto.com
https://www.townmoto.com
www.speedmotoco.com
www.lostapostle.ca/
www.sparckmoto.com
Top Bottom