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170cc Big Bore Piston Kit Time Line

15130 Views 37 Replies 25 Participants Last post by  Mike R
Guys,
I had a major notifications from my piston & sleeve suppliers yesterday & today. I'll have the prototype 170cc pistons kits in about 4 to 5 weeks. So testing will take place over the month of December. I am trying to have production pistons ready for sale with the first group of big bore cylinders machined, ready for sale, by the end of Feb. If you are interested in the kit, and would like to see a CAD rendering of the piston, email me at [email protected], and I'll email it back. I'll also save the emails in a special folder, just for riders interested in the big bore piston kit. I'll keep anyone on file updated as to what's going on. Please include your shipping address. Sorry, I do not have good pricing information yet. It's just to early. So soon as I get an idea of the REAL machining costs to the cylinder, I will be able to give everyone a price.
We are moving forward!
Brian
SRD
PS, Think about this question for me:
Would you rather re-bore YOUR cylinder, or exchange it for a finished cylinder, or just buy the new one outright. The core charge will be $72.00, my cost for the cylinders with shipping?
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I already have a ported head done. I'm going to flow it with the 61mm cylinder, but with the stock valves first, and then the larger valves second. The only reason that it is not flow tested it yet, is that they are moving the flow bench at work to a new room, and it won't be working until late next week. The 61mm head gasket will be done in about 4 weeks. The throttle body flows plenty of air, 90 CFM, so it will not be a restriction. The air box with the metal plate/screen removed is OK the way it is. I'll have a CFM number on all these parts by the hollidays. I know that the secondary rubber tube in the air box is better removed, but then it needs the velo stack, that I made, so I'm having that quoted right now. The cam is another story: I talked to MegaCycle Cams 2 weeks ago. They probably have more usable grinds in stock than anyone else, but they didn't seem to want to do it, unless I had about 50 cams done at once. I'll call them back. Anyone of the larger diameter,1", head pipe exhaust out there will work OK. I have my test exhaust set at tuned length, and I can feel a difference. The dyno testing wil get done over the hollidays.
Brian
Yep, it's official. I'm gonna hold out on ALL mods until you have a package put together. I just hope that your exhaust is a low mount so my honey doesn't burn her pretty legs on it when she rides with me.
Brian , do you think the Bazzaz Z-Fi would be a good purchase for a stock bike ? Will the fuel management system work with all the goods you are making ?

Thanks for your time
Brian , do you think the Bazzaz Z-Fi would be a good purchase for a stock bike ? Will the fuel management system work with all the goods you are making ?

Thanks for your time

pretty sure that the bazzaz z-fi can be adjusted to anything you throw at it and they also have some auto tune setup as well that you can buy separate. id shoot josef an email [email protected] as he's the guy I met at the aim expo and knows his stuff for sure.
All these kits etc will not last long without properly tuned fi.
If you don't want tons of questionable headaches, warranty claims if you offer one, and bad forum press I would be reluctant to sell em without a box.
If bought separately an as-is or something guarantee.
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no doubt.

we dont really have many options for tuning the fi right now. I'm not sure how those who have ran a bore kit or anything big like a turbo is dealing with that right now.
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Everyone is getting ancy for a quality big bore kit. Wow. Y'all just need to RDWHAHB.
The Honda FI System

OK,
I have the most experience with DynoJet Power Commanders, having had them on 3 different bikes, all with great success. I know that DynoJet is bringing out a box for the Grom. There was one male/female connector that they were asking a supplier to get, or mold. Probably about 3 months away. I'll check this week.
I have a $600.00 Daytona dual O2 sensor system that is very accurate. So I can monitor the mixture regardless of the Honda system. I have already mounted on the bike and used it. If the system does not compensate for the big bore kit, I will change out the injector for a slightly larger Honda injector, and run all the tests again. If it needs a ECU black box, I'll get one, and make a file that works well, and give it with the big bore kit. I plan to test the kit with the stock exhaust, and my replacement exhaust system. I'm in line to get one of the first DynoJet kits.
One of the things that I discovered when I used the O2 sensor was that the system goes to 12.8/13.2 to 1 when you open the throttle to WOT. That's a perfect ratio for power. I can't test every exhaust system, but if you guys send out a few of the European systems, I'll test them and see if the file is different, and then provide you with a file.

I will not sell this kit without a fuel curve that works, period. If someone decides to pull off the whole induction system, and run a velocity stack, they are on their own, but I'll still try to help. If someone decides to run the big bore kit at 9700, and not to 8700, like it's designed for, I can't help them. Please remember I am increasing the displacement by about 36%. There will be no reason to rev the piss out of the 170 kit. Think small block Chevy / big block Chevy. There should be so much more torque, that I plan to change the countershaft sprocket to a 16 tooth, because it will pull it.
Brian
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Brian,

What does A well engineered American made upgrade like this cost? Obviously you don't know what will be needed just yet but, are we talking in the $500 range $1000 range or $1500?

Ill start saving regardless.
Love the way you are approaching this. I'm in!
This sounds great well worth the time and effort to bring a great product. This will go along way no matter the cost of the product because we know we have a actual person that we can contact and help with any problems. Im down to ride the piss out of my grom the way it sits and spend my money when this come to market...
Sign me up. Plug and play is my wish. Ballpark $ amount would help my budget.....
since this thread is probably going to get very long. when you get the first photos. make a new thread so its easier to find !
Where do I send my cylinder? And when?
I'm very interested in this 170 cc upgrade system. I would also like to stay stock looking as possible, such as stock exhaust system and air cleaner system. Maybe upgrade the air cleaner system if needed.

I want a sleeper Grom that will be a hoot from light to light and will at least pull my 210 lbs weight to a good 75mph.

thanks for the update and tech info
I don't think changing your exhaust puts you out of sleeper status.

Just dont get a very loud one and you should be good :) :motorcycle3_smilie:
I'm gonna save like $700 juuuust incase it's more expensive than expected. A 170cc is going to put the groms fun factor off the charts.


Sent from Motorcycle.com Free App
The Honda FI System

OK,
I have the most experience with DynoJet Power Commanders, having had them on 3 different bikes, all with great success. I know that DynoJet is bringing out a box for the Grom. There was one male/female connector that they were asking a supplier to get, or mold. Probably about 3 months away. I'll check this week.
I have a $600.00 Daytona dual O2 sensor system that is very accurate. So I can monitor the mixture regardless of the Honda system. I have already mounted on the bike and used it. If the system does not compensate for the big bore kit, I will change out the injector for a slightly larger Honda injector, and run all the tests again. If it needs a ECU black box, I'll get one, and make a file that works well, and give it with the big bore kit. I plan to test the kit with the stock exhaust, and my replacement exhaust system. I'm in line to get one of the first DynoJet kits.
One of the things that I discovered when I used the O2 sensor was that the system goes to 12.8/13.2 to 1 when you open the throttle to WOT. That's a perfect ratio for power. I can't test every exhaust system, but if you guys send out a few of the European systems, I'll test them and see if the file is different, and then provide you with a file.

I will not sell this kit without a fuel curve that works, period. If someone decides to pull off the whole induction system, and run a velocity stack, they are on their own, but I'll still try to help. If someone decides to run the big bore kit at 9700, and not to 8700, like it's designed for, I can't help them. Please remember I am increasing the displacement by about 36%. There will be no reason to rev the piss out of the 170 kit. Think small block Chevy / big block Chevy. There should be so much more torque, that I plan to change the countershaft sprocket to a 16 tooth, because it will pull it.
Brian
Hello to you, I just did a 170 kit and a filter intake and already dual carbon exhaust, the power commander worked fine with stoke motor now sputtering off the bottom and Def feels starving for fuel. [email protected]
Any shops you know near southern California that can mess with it ?? Mike
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