BakerBoy
It's all small stuff.
I completed some needed maintenance on the '04 ST this weekend, after 11.3k miles. This was my first time with all the fairing removed and tank+airbox removed, and getting it disassembled & reassembled properly seemed as significant as the actual maintenance! I found lots of good information on this forum...an example being to ensure that fuel was down to 1 bar. :bow1:
Sorry for the long post, but I thought I'd describe some of the things noted during the work. I'd changed the tires, done oil/filter changes, and performed clutch/brake fluid flushes on this bike, but this was my first time diving this deep with this bike. Hopefully some of you out there who may be on the fence about doing similar work yourself may benefit from some of these points and can then decide for yourself that it is doable. I used the Honda ST1300 service manual, plus the coolant and thermostat procedures found on this site.
During disassembly I put all the fasteners/screws/rivets back into their original holes and taped over them. I also labeled all parts/fairing pieces as L or R before hanging them out of the way for the service.
Coolant changout. After going to numerous hardware stores and auto shops, I didn't find an alternate source for the 6.5mm copper drain bolt washer so I bought a handful at a Honda motorcycle shop for $2.74 each. I also bought the Honda automotive "Type 2" 50/50 premix coolant, in faST blue for $12.92 (FYI, Acura sells the exact same coolant at the same price).
As many of you have experienced, getting that large hose off the radiator inlet was quite a chore. And when it comes free coolant splashes everywhere. I felt prepared with lots of towels, floor paper, and drain pans, but coolant still went everywhere, including when the block drain bolts were removed. Most of it was cleaned up by the time I took this picture:
After draining the system, I pulled the radiator and cleaned it out in the kitchen sink (wife didn't know
)--lots of bug goo on the outside, and black paint was peeling off inside of the connections. An example of that paint is seen here:
The overflow bottle had a fine grit with some translucent scale/flakes in it...looked a bit like hard water deposits you could scrape off a faucet aerator. That stuff came out of the overflow bottle with some shaking, but I wondered how much was left inside the engine.
After reinstalling, reconnecting, and washing the coolant off the engine surfaces, I filled it up with distilled water and ran it up to temperature to flush it more fully. It was surprising how much additional color (residual coolant) and some debris came out when I drained the distilled water. An extra step, but it appeared worth it.
Thermostat changeout. The existing thermostat was still working properly; a picture of it and original o-ring before removal are shown below (note the debris around the thermostat and the dried coolant around the exterior of the o-ring). But after seeing what was in the coolant, the overflow bottle, and on the old thermostat, I installed a new TurboCity thermostat I'd just ordered on speculation. The thermostat housing cover had been leaking past the o-ring seal (see 2nd picture below, taken before opening the housing), among other leaks. And the new o-ring provided with the TurboCity thermostat appeared to be of proper size, but both the old and new o-rings just 'seem' skinny for the application. I used two dabs of clear RTV silcone sealant on the new o-ring when putting it back together...time will tell if it stays sealed. I will be finding and acquiring a slightly thicker o-ring on speculation that I'll be back in there soon. I would have purchased a stock Honda seal to have on hand, but I waited too long to inquire and they were not 'stock' items. IMHO, The stock 43.5x2mm o-ring may need to be 2.5 or 3mm thick.
Search for Coolant Leaks. For perspective, I'd only needed to add 1 cup or so of coolant over the years so I wasn't concerned. Yet, several leaks were found, all in 'the abyss' below the carb bodies. You can see one such leak in the background in the photo immediately above. A couple leaks had very loose hose clamps, and a couple leaks were at connections where there were sufficiently tight hose clamps. As shown above, the thermostat housing cover was also leaking. I found no leaks at the water pump or water pump hose connections. As others have surmised, based on the trail of dried coolant down the front of the engine, it would be easy to mis-diagnose that the water pump seal was leaking.
Fuel Pressure Regulator. The TurboCity FPR went in nicely, good instructions provided with it. Only a teaspoon or so of gas dripped out during the swap--but I had the fuel level very low in the lower tank. My goal in installing it was to lessen that abrupt power surge when cracking the throttle.
Starter Valve Synch. The air funnel base screws came out without any problem using an impact screwdriver. While there, I readjusted the throttle cable play by transferring the adjustments I'd made over the years from the upper expansion nut set (by the hand-grip) down to the cable slack adjustment at the carb bodies (seen at the top left of the throttle bodies in the picture below). The bigger challenge was getting the small vacuum lines off of that 5-way vacuum connector--the factory installed vacuum line length was short enough to make that task difficult. After warming up the bike, cylinders 2 & 3 had slight higher vacuum than 1, and 4 was slightly lower than 1. A couple clicks of the adjustment screws and it balanced out. By the way, I use a Morgan Carbtune Pro for the synch.
Counter Balancers Adjusted. I followed the instructions, finding that they were about right to begin with. Honestly, I had a tough time hearing the 'whine' side of adjustment, but hearing the 'rough, gravelly' side was easy enough.
Miscellany. The spring clamp (item 26) at the bottom of the short, large fuel hose betwen the upper and lower tank was very difficult to get set properly when reinstalling the upper fuel tank . The service manual calls for that hose (item 8) and spring clamp to be replaced...I'll have to plan for that next time. Do any of you out there replace those every time? Or have an alternative?
I find that the 4 lower fairing plastic rivets which hang down under the fairing get beat up quickly by rock hits & heat (and coolant dripping on them may embrittle them), so a couple years ago I'd improvised a zip-tie that fastens the 2 lower fairings and 2 middle cowls where they come together. The zip-tie held well and I found that it was all that held the fairing together when I started disassembling the bike for this service. So I again used a zip tie, but also used 2 new plastic rivets and I'll watch closer this time to see whether those rivets survive this time around without coolant dripping on them.
The radiator has taken a number of hard impacts, one in particular probably would have led to a leak if it had hit just a 1/4" lower. I spent quite a bit of time straightening out the fins, and doing that convinced me to get a new grill/guard shortly.
I didn't have suspicion that I'd feel a huge improvement in performance as the bike has continued to run very good since new. After getting the bike reassembled and then test riding it yesterday, the power surge does seems to be a bit softer, and overall it feels a bit smoother. That softer response is probably from the combination of starter valve synch, counter balancer adj, and new FPR.
Sometime later this summer is another set of tires, another brake/clutch fluid flush, and the dreaded valve clearance check (that's the one I'm not looking forward to).
I did similar service on my V-Strom a couple weeks ago, so now both the MiSTress and PaSTromi are good for lotsa miles!
Sorry for the long post, but I thought I'd describe some of the things noted during the work. I'd changed the tires, done oil/filter changes, and performed clutch/brake fluid flushes on this bike, but this was my first time diving this deep with this bike. Hopefully some of you out there who may be on the fence about doing similar work yourself may benefit from some of these points and can then decide for yourself that it is doable. I used the Honda ST1300 service manual, plus the coolant and thermostat procedures found on this site.
During disassembly I put all the fasteners/screws/rivets back into their original holes and taped over them. I also labeled all parts/fairing pieces as L or R before hanging them out of the way for the service.
Coolant changout. After going to numerous hardware stores and auto shops, I didn't find an alternate source for the 6.5mm copper drain bolt washer so I bought a handful at a Honda motorcycle shop for $2.74 each. I also bought the Honda automotive "Type 2" 50/50 premix coolant, in faST blue for $12.92 (FYI, Acura sells the exact same coolant at the same price).
As many of you have experienced, getting that large hose off the radiator inlet was quite a chore. And when it comes free coolant splashes everywhere. I felt prepared with lots of towels, floor paper, and drain pans, but coolant still went everywhere, including when the block drain bolts were removed. Most of it was cleaned up by the time I took this picture:
After draining the system, I pulled the radiator and cleaned it out in the kitchen sink (wife didn't know
)--lots of bug goo on the outside, and black paint was peeling off inside of the connections. An example of that paint is seen here:The overflow bottle had a fine grit with some translucent scale/flakes in it...looked a bit like hard water deposits you could scrape off a faucet aerator. That stuff came out of the overflow bottle with some shaking, but I wondered how much was left inside the engine.
After reinstalling, reconnecting, and washing the coolant off the engine surfaces, I filled it up with distilled water and ran it up to temperature to flush it more fully. It was surprising how much additional color (residual coolant) and some debris came out when I drained the distilled water. An extra step, but it appeared worth it.
Thermostat changeout. The existing thermostat was still working properly; a picture of it and original o-ring before removal are shown below (note the debris around the thermostat and the dried coolant around the exterior of the o-ring). But after seeing what was in the coolant, the overflow bottle, and on the old thermostat, I installed a new TurboCity thermostat I'd just ordered on speculation. The thermostat housing cover had been leaking past the o-ring seal (see 2nd picture below, taken before opening the housing), among other leaks. And the new o-ring provided with the TurboCity thermostat appeared to be of proper size, but both the old and new o-rings just 'seem' skinny for the application. I used two dabs of clear RTV silcone sealant on the new o-ring when putting it back together...time will tell if it stays sealed. I will be finding and acquiring a slightly thicker o-ring on speculation that I'll be back in there soon. I would have purchased a stock Honda seal to have on hand, but I waited too long to inquire and they were not 'stock' items. IMHO, The stock 43.5x2mm o-ring may need to be 2.5 or 3mm thick.
Search for Coolant Leaks. For perspective, I'd only needed to add 1 cup or so of coolant over the years so I wasn't concerned. Yet, several leaks were found, all in 'the abyss' below the carb bodies. You can see one such leak in the background in the photo immediately above. A couple leaks had very loose hose clamps, and a couple leaks were at connections where there were sufficiently tight hose clamps. As shown above, the thermostat housing cover was also leaking. I found no leaks at the water pump or water pump hose connections. As others have surmised, based on the trail of dried coolant down the front of the engine, it would be easy to mis-diagnose that the water pump seal was leaking.
Fuel Pressure Regulator. The TurboCity FPR went in nicely, good instructions provided with it. Only a teaspoon or so of gas dripped out during the swap--but I had the fuel level very low in the lower tank. My goal in installing it was to lessen that abrupt power surge when cracking the throttle.
Starter Valve Synch. The air funnel base screws came out without any problem using an impact screwdriver. While there, I readjusted the throttle cable play by transferring the adjustments I'd made over the years from the upper expansion nut set (by the hand-grip) down to the cable slack adjustment at the carb bodies (seen at the top left of the throttle bodies in the picture below). The bigger challenge was getting the small vacuum lines off of that 5-way vacuum connector--the factory installed vacuum line length was short enough to make that task difficult. After warming up the bike, cylinders 2 & 3 had slight higher vacuum than 1, and 4 was slightly lower than 1. A couple clicks of the adjustment screws and it balanced out. By the way, I use a Morgan Carbtune Pro for the synch.
Counter Balancers Adjusted. I followed the instructions, finding that they were about right to begin with. Honestly, I had a tough time hearing the 'whine' side of adjustment, but hearing the 'rough, gravelly' side was easy enough.
Miscellany. The spring clamp (item 26) at the bottom of the short, large fuel hose betwen the upper and lower tank was very difficult to get set properly when reinstalling the upper fuel tank . The service manual calls for that hose (item 8) and spring clamp to be replaced...I'll have to plan for that next time. Do any of you out there replace those every time? Or have an alternative?
I find that the 4 lower fairing plastic rivets which hang down under the fairing get beat up quickly by rock hits & heat (and coolant dripping on them may embrittle them), so a couple years ago I'd improvised a zip-tie that fastens the 2 lower fairings and 2 middle cowls where they come together. The zip-tie held well and I found that it was all that held the fairing together when I started disassembling the bike for this service. So I again used a zip tie, but also used 2 new plastic rivets and I'll watch closer this time to see whether those rivets survive this time around without coolant dripping on them.
The radiator has taken a number of hard impacts, one in particular probably would have led to a leak if it had hit just a 1/4" lower. I spent quite a bit of time straightening out the fins, and doing that convinced me to get a new grill/guard shortly.
I didn't have suspicion that I'd feel a huge improvement in performance as the bike has continued to run very good since new. After getting the bike reassembled and then test riding it yesterday, the power surge does seems to be a bit softer, and overall it feels a bit smoother. That softer response is probably from the combination of starter valve synch, counter balancer adj, and new FPR.
Sometime later this summer is another set of tires, another brake/clutch fluid flush, and the dreaded valve clearance check (that's the one I'm not looking forward to).
I did similar service on my V-Strom a couple weeks ago, so now both the MiSTress and PaSTromi are good for lotsa miles!
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