Spada Speed Modifications

Hi all! new member here posting for the first time.

I recently got a honda spada, and so far I really love this little bike. It's so light and handles really well, but it doesn't go nearly fast enough for me. I was thinking I might tweak it a bit to make it go a little faster, so I was hoping someone here might have tried to do the same thing.

the first things that came to mind were 4-barrel carbs, those trumpet shaped intakes, exhaust, mill down the head to increase the compression ratio, removing the baffles in the exhaust...

does anyone have any pointers or experience they can share with me before I begin this project?

thanks very much!
Phil

I googled it. It is a 250cc. Nice looking scoot.

Phil, I know you like this bike but you'll throw thousands of dollars to get more power and you'll still only end up with maybe a 300cc. your best bang for the buck is ride it around for a few years then trade it in. Honda's have a lot of great bikes, Try one of those cbr600 next.

This is the way most of us did it. Our first bike was a small one and we have great memories of them but we eventually upgraded to larger and larger (faster and faster) bikes.

Well, I hope that gives you food for thought. Remember it's just my two cents worth.

Good luck.

Welcome to Bike Talk, Phil
I looked at some specs listed for a older Honda Spada. It was listed to have 11.0:1 compression ratio, and produce 40hp @ 12000rpm. With that much compression at those rpm’s you could get in to valve clearance trouble very quick. The top speed is listed as 111.8 mph. if you are not able to get that then you could consider a sprocket change to lower your overall gear ratio. It would take a little trial and error or luck, but If your bike has a tach then change the sprocket size to where you can tach it out in high gear, or find a ratio that you could live with. If it will run the 111.8 then add Nitrous and go out in style. You’ll blow the motor but you probably wont be around to worry about it. Haha just joking.:roflmao: Have fun and safe riding!

thanks RaKs! I hadn't considered adjusting the gear ratio - that sounds like a fairly inexpensive approach to this situation. do you think I could pull a sprocket off of another bike, or will this end up being a custom-milling job? also, do you think replacing the intake/exhaust might make a difference? I don't know how well these bikes breath stock...

tom - I know I could spend a lot of money for very small gains, but my aim for this project is to do this cheaply. I figure milling the head is cheap, and removing the baffles is cheap, etc. as for the carbs I reckon I might be able to hit up the wrecking yard and pull something off of a deceased bike.

Yeah I didn't realize the compression was already so high on the spada. I should have been using higher octane fuel this whole time. What about the carbs? Can anyone recomend a resource to figure out what carbs I can scavenge off another bike to improve the performance on the spada? I'm not looking for a whole lot of top end performance (after all it's a v-twin), I would really be satisfied with some speed off the line. I thought v-twins were better for low-end torque anyways, so it shouldn't be impossible, right? I just want to make this girl stand up on her back tire, that's all...

Also has anyone used those trumpet shaped intakes? Do they actually make a difference? Or should I just remove the airbox (I assume there's an airbox) and replace it with a K&N or something similar.

As for the exhaust, does removing the baffles actually make the bike go faster or merely sound faster?

I'll post some pics once I actually get this project started. I'm excited to make this bike a bit faster because I love driving sleepers. I tuned my old Volvo up to 250 bhp really cheaply (that's why I love scrap yards...). Nothing ever beat the expressions on peoples' faces after they'd been beaten by my big ole turbo-brick

To start with if I understand it right you want a bike with some low RPM balls. Although torque is not totally dependent on size (volume, cubic inches, cubic centimeters) there is a corresponding ratio. When you hear of V-Twin motors having a lot of torque the references are made to engines that are designed for use at lower RPMs Harley’s are set up for around 6000rpm, the spada is set up for around 13500rpm. Then there is the size issue the Spada has 249cc or 15.19 cubic inches, my Harley has 1803cc or 110 cubic inches. I’ll help you with the math, mine is over seven times bigger than yours, and the chicks are right when they say size matters!
As far as trying to help the performance it just my opinion but I think that anything you do would be counter productive and mess up a fun toy. Sometimes you just have to face the facts “you have a mini-bike” and although it’s probably a lot of fun it will never be the powerhouse that you are hoping for. It’s just my opinion so take it for what it’s worth to you.

It sounds like you got the tinkering passion. In that case, I don't think you're gonna let any of us stop ya. I think you know what you're getting your self into, so I say go for it. Sounds like a fun project anyway as long as you don't break the bank.

As far as carbs go. Rip them apart and see if you can learn about changing the jet size. If so, then do that at the same time you punch out the baffles in the mufflers. But jet size is going to be a total guess on your part and after you change this stuff your going to go through a lot of trial getting it to idle and run right again. So, my only advice is to do it in baby steps.

If you want to change carbs then measure the diameter of the carbs you got and try finding carbs from a bigger Honda engine and about the same year then just try it and see what happens. I don't think there are any Honda carb experts reading this forum.

Let us know how it goes since you got us all worked up to know.