Unknown air box mod
Unknown air box mod
I recently purchased a 1998 Superhawk with the intent of using it for track days and occasionally on the street. The bike was not running when I made the purchase. It's been sitting in a garage for a few years, had old gas in the tank, carbs needed cleaning, and it needed a battery. Other than these and an overall thorough cleaning, it appears to be in great shape and came with some nice upgrades.
As soon as I made the purchase I joined SH Forum and started reading about the SH. It's been very helpful to have some detailed instructions and photos to follow during carb removal and cleaning. I have a Honda manual too, but it's always good to read from the experiences of a dedicated group too.
I have the carbs off still but after disassembly, a good overnight soak in Yamalube, and reassembly, and some cleaning, I think they are ready to go back on now. I noticed during disassembly that what I was seeing didn't match the pictures in the manual and after some searches here I found quickly that there has been some modifications done outside of what was discussed during the sale inspection.
I found during carb disassembly and in the paperwork I got with the bike that there is an aftermarket Micron jet kit installed, the PAIR system has been removed, and there is some changes to the air box. After some further searching, I have not found any pictures or discription of the air box mod that has been done. I have the trumpets removed in the attached pic.
My concern is that I'll put it all back together and it will not run or run poorly. It would help if I knew what's been done, so here's a pic of the air box with two pod filters and two plastic covers over the corner breather tubes. There are also block-off plates engraved with "TBR" on the valve covers.
Can anyone help identify if this mod? Is it a common mod? How will it affect the bike from stock?
I could always buy some parts on eBay and put it back to stock, but it may just run fine like this. I could assume it was running before it was put away a few years ago but I'd rather be ready to with a plan when I put it back together and it runs poorly since its kind of a pain to pull the carbs.
Since I've got the carbs off I also performed the TPS mod and added a fitting to make carb balancing easier. I'm planning to also do the MCCT mod. There are several kits available for the MCCT mod. Any recommendations?
Bill
Annapolis, MD
As soon as I made the purchase I joined SH Forum and started reading about the SH. It's been very helpful to have some detailed instructions and photos to follow during carb removal and cleaning. I have a Honda manual too, but it's always good to read from the experiences of a dedicated group too.
I have the carbs off still but after disassembly, a good overnight soak in Yamalube, and reassembly, and some cleaning, I think they are ready to go back on now. I noticed during disassembly that what I was seeing didn't match the pictures in the manual and after some searches here I found quickly that there has been some modifications done outside of what was discussed during the sale inspection.
I found during carb disassembly and in the paperwork I got with the bike that there is an aftermarket Micron jet kit installed, the PAIR system has been removed, and there is some changes to the air box. After some further searching, I have not found any pictures or discription of the air box mod that has been done. I have the trumpets removed in the attached pic.
My concern is that I'll put it all back together and it will not run or run poorly. It would help if I knew what's been done, so here's a pic of the air box with two pod filters and two plastic covers over the corner breather tubes. There are also block-off plates engraved with "TBR" on the valve covers.
Can anyone help identify if this mod? Is it a common mod? How will it affect the bike from stock?
I could always buy some parts on eBay and put it back to stock, but it may just run fine like this. I could assume it was running before it was put away a few years ago but I'd rather be ready to with a plan when I put it back together and it runs poorly since its kind of a pain to pull the carbs.
Since I've got the carbs off I also performed the TPS mod and added a fitting to make carb balancing easier. I'm planning to also do the MCCT mod. There are several kits available for the MCCT mod. Any recommendations?
Bill
Annapolis, MD
Airbox is standard. The block off plates are for the K&N filter it has. The breather filters from the motor vent tubes are not needed. Air in there is already filtered.
If the jet kit is sorted it should run fine.
If the jet kit is sorted it should run fine.
Those pod filters don't even need to be inside the airbox, since that is filtered air. To make removing and installing (mostly installing) the airbox easier when doing carb tuning, take those hoses from the valve covers and shorten them a bit. Then put those pod filters on the end like in the pictures below. You honestly do not get any oil coming out of the filters.
I didn't think Two Brothers Racing made PAIR block off plates. Maybe TBR stands for something else? Either way, they are block off plates and all the PAIR crap can be removed and capped off.
For MCCT's contact superdutyd. He has made some very nice and well thought out MCCT's.


I didn't think Two Brothers Racing made PAIR block off plates. Maybe TBR stands for something else? Either way, they are block off plates and all the PAIR crap can be removed and capped off.
For MCCT's contact superdutyd. He has made some very nice and well thought out MCCT's.


Thanks to everyone for the replies - all very helpful. I was a little lost about what had been removed and what could be removed but I think it's all understood now.
I've settled on modifying the OEM CCTs as described by calitoz here: https://www.superhawkforum.com/forum...ual-one-22711/
But I had to order the hardware on Amazon because the local True Value was out of stainless M6 x 40 bolts. They usually have everything I need.
I don't think I'll change anything on the air box until I've get her runnin'. I have to assume everything was tuned well before she was put away in the garage so I'll start here as my baseline. I ordered the little D socket to adjust the pilot jet but I didn't order the $70 tool that holds the socket at 90 degrees and let's you adjust without removing the carbs, so I'm hoping everything is adjust well so I don't need to pull the carbs again.
I hoping to have everything back together to light her off next weekend. The only other mods I have plans for are stiffer front springs, a rear shock, and maybe a new seat.
Bill
Annapolis, MD
I've settled on modifying the OEM CCTs as described by calitoz here: https://www.superhawkforum.com/forum...ual-one-22711/
But I had to order the hardware on Amazon because the local True Value was out of stainless M6 x 40 bolts. They usually have everything I need.
I don't think I'll change anything on the air box until I've get her runnin'. I have to assume everything was tuned well before she was put away in the garage so I'll start here as my baseline. I ordered the little D socket to adjust the pilot jet but I didn't order the $70 tool that holds the socket at 90 degrees and let's you adjust without removing the carbs, so I'm hoping everything is adjust well so I don't need to pull the carbs again.
I hoping to have everything back together to light her off next weekend. The only other mods I have plans for are stiffer front springs, a rear shock, and maybe a new seat.
Bill
Annapolis, MD
I see you found Jack Flash's thumb screws. They are nice!
Below is a tutorial on how to install MCCT's. This is a fantastic link, because it shows lots of pictures along the way. It will also show you what the inside of a stock airbox looks like. You can remove those small pod filters. Those pod filters, which are redundant, will only make turbulence inside the airbox and possibly cause issues. These CV carbs do not like turbulence.
www.vtr1000.org ? View topic - Manual Cam Chain Tensioner Installation Guide (MCCT's)
If all the PAIR stuff had been removed, make sure the nipple (~3/8" dia.) on the bottom of the airbox has been closed off. If not, then unfiltered air is getting into your airbox and into your engine.
EDIT: When you check the timing of the engine, many Superhawk owners have had the engine cover bung strip out, because Honda made them out of cheese. Below is an eBay auction for a replacement. They are made from aluminum and levels better than the original.
http://www.ebay.com/itm/Crankcase-Co...item33af2b3bcc
Below is a tutorial on how to install MCCT's. This is a fantastic link, because it shows lots of pictures along the way. It will also show you what the inside of a stock airbox looks like. You can remove those small pod filters. Those pod filters, which are redundant, will only make turbulence inside the airbox and possibly cause issues. These CV carbs do not like turbulence.
www.vtr1000.org ? View topic - Manual Cam Chain Tensioner Installation Guide (MCCT's)
If all the PAIR stuff had been removed, make sure the nipple (~3/8" dia.) on the bottom of the airbox has been closed off. If not, then unfiltered air is getting into your airbox and into your engine.
EDIT: When you check the timing of the engine, many Superhawk owners have had the engine cover bung strip out, because Honda made them out of cheese. Below is an eBay auction for a replacement. They are made from aluminum and levels better than the original.
http://www.ebay.com/itm/Crankcase-Co...item33af2b3bcc
Last edited by CruxGNZ; Apr 17, 2016 at 08:52 PM. Reason: Moar info
Thanks CruzGNZ. That's exactly the guide I've been using for the MCCT install along with the OEM CCT mod by carlitoz. That's definitely the most clear instructions I've found as the search tool is not super friendly here.
I checked the air box and found that vent hole plugged with some duct tape. Thanks again. I didn't even notice that one. I'll get a proper plug on that.
I'm sure those new pilots from Jack Flash will make adjustments a lot easier and they are a bargain at $30. I got the D socket today and pulled the pilots out to see. They were sooo full of goo despite an overnight soak in Yamalube. I doubt running fresh gas through would have cleaned that up.
I managed to get the timing and drive covers off with no damage but they were both super tight. I needed a two foot breaker bar on the drive cover. A little valve grinding compound on the correct Allen wrench worked well. I'll put anti seize on before I tighten them back up.
I can't wait to hear this thing run. The suspense is killing me.
Bill
Annapolis, MD
I checked the air box and found that vent hole plugged with some duct tape. Thanks again. I didn't even notice that one. I'll get a proper plug on that.
I'm sure those new pilots from Jack Flash will make adjustments a lot easier and they are a bargain at $30. I got the D socket today and pulled the pilots out to see. They were sooo full of goo despite an overnight soak in Yamalube. I doubt running fresh gas through would have cleaned that up.
I managed to get the timing and drive covers off with no damage but they were both super tight. I needed a two foot breaker bar on the drive cover. A little valve grinding compound on the correct Allen wrench worked well. I'll put anti seize on before I tighten them back up.
I can't wait to hear this thing run. The suspense is killing me.
Bill
Annapolis, MD
I managed to get the timing and drive covers off with no damage but they were both super tight. I needed a two foot breaker bar on the drive cover. A little valve grinding compound on the correct Allen wrench worked well. I'll put anti seize on before I tighten them back up.
Bill
Annapolis, MD
Bill
Annapolis, MD
Yes some anti sieze will help if the plug is over tighten or in a harsh corrosive environment (think winter salted streets) However if the plug is tightened correctly no addition anti sieze treatment is required.
I ordered a set of pilot jets from Jack Flash that should arrive soon, but I just couldn't wait to fire this bike up today. I put the carbs, air box, and tank back on and put in some fresh gas. It only took a few tries (after turning the peacock back 'ON') to get her started.
Wow! Despite running very rich it sounds great. Very loud compared to my stock V65 Sabre.
I'm going to wait until the new jets arrive to pull the carbs again and start tuning.
Bill
Annapolis, MD
Wow! Despite running very rich it sounds great. Very loud compared to my stock V65 Sabre.
I'm going to wait until the new jets arrive to pull the carbs again and start tuning.
Bill
Annapolis, MD
Motorcycles are not meant to sit idle for years.
I can't believe that I didn't check the clutch until now, but I guess I didn't and it's definitely not working. I opened the reservoir and found it totally clogged with gunk - thick brown gunk. I cleaned it out and completely cleaned out the clutch MC as well. I tried to bleed out the remaining but had no luck. I opened the master slave and found it too clogged with gunk.
I'm still waiting for clutch parts, but received the adjustable pilots from Jack and installed. I've got everything back together now except the clutch master and the fairings.
It's a good thing forecast is for rain this week.
Bill
Annapolis, MD
It's a good thing forecast is for rain this week.
Bill
Annapolis, MD
I ordered a set of pilot jets from Jack Flash that should arrive soon, but I just couldn't wait to fire this bike up today. I put the carbs, air box, and tank back on and put in some fresh gas. It only took a few tries (after turning the peacock back 'ON') to get her started..
Pull harder.
Yes. Both of those suggestions are good ones. I remember loosening the clamps on the carbs and finding the carbs still very difficult to pull off. The rubber boots get very stiff. Do not pry the carbs off with anything. You’ll only end up damaging something. Wiggle them from side to side and pull up. The back carb should come up first.
Getting them back on can be just as difficult. Make sure the bottom clamps (the clamps attached to the head) are tight before you reinstall the carbs. Also, make sure they’re all the way on before you re-tighten the top clamps. They should ‘snap’ into the hardened groove in the boots. You can use a mirror and flashlight to see if they’re on all the way. If not, you’ll have an intake leak and it won’t run well.
Good luck.
Getting them back on can be just as difficult. Make sure the bottom clamps (the clamps attached to the head) are tight before you reinstall the carbs. Also, make sure they’re all the way on before you re-tighten the top clamps. They should ‘snap’ into the hardened groove in the boots. You can use a mirror and flashlight to see if they’re on all the way. If not, you’ll have an intake leak and it won’t run well.
Good luck.
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