Separate names with a comma.
Discussion in 'Thumpers' started by Fishnbiker, Dec 12, 2019.
Anyone out there know if there's any other fix to the problem of a worn connecting rod small end (wrist pin end) other than repkacing the connecting rod, which I'm pretty sure requires pressing the crank apart? Seems like Japan for cost reasons or whatever chose not to put a replaceable wrist pin bushing in their rods instead running the wrist pin in the aluminum that the rods made of. ???? wiguzziman
Running the pin direct in the rod is a very common way of doing it for 4 stroke engines. All the way from Harleys to high revving and high power race bikes.
Usually the oil film between the rod and pin provides enough lubrication and no bearing or bushing is needed (with a bushing you create 2 rubbing surfaces that might actually wear down faster than 1).
You can have your small end welded to get some material back but I do not know the costs nor the quality of that. Might be better to fit another crank (not too hard to come by because usually the top end of the motor craps out before the crank) or get yourself a nice aftermarket rod.
Thanks for the response. I was hoping for some "new fangled high tech" solution to this, but I guess technology hasn't caught up to this issue yet. From the checking I've done, a new rod kit, plus the crank work involved to install the new rod is bumping the $300.00 (US) range pretty hard. I do have another lower end motor assembly (cases, tranny, crank, cylinder, ect.). Guess I'll have to check the condition of that crank assembly before I go spending a bunch of money.
Thanks again! wiguzziman
You can always go to a machine shop and have them take a look at it. Might be possible to open the hole in the small end and pressfit a bushing in there. You will probably have to take the crank out for them to do so and a secondhand crank might be faster and cheaper.
I just completed a total overhaul of my CBR front forks. Also fitted YSS PD-valves (Racetech gold valve clones).
Replaced the oil and dust seal, top and bottom bushing, top bolt oil O-ring, bottom crush ring and drilled some new holes in the damper rods to make sure the PD-valves can do their thing.
I've worked on cartridge and USD forks before and really these conventional forks are the easiest ever, they are the same design as the FT so for everyone who is in doubt about doing this, it really is very very easy.
Next to that I finished welding my exhaust and painted it with some heat resistant black
When doing this I also drilled some holes in the headers to plug weld the inner tubes that were rusted loose. This method works pretty good so would definitely recommend this when you have the rattling inner tubes.
Last but not least I fitted new rubber to the bike
I went with 110/70/17 and 140/70/17 Bridgestone RS10s.
Has anyone tried a Mikuni Flatslide carb without acceleration pump on the FT? (so not the RS but the TMX)
Is it possible to get it running well? Or do you suffer from a too lean mixture on full throttle on low revs?
Actually I have a 34mm Mikuni Flat Slide carb (no accelerator pump) on my Road Racer Replica project bike that I recently completed. I picked it up at a local swap meet a few years back for $50.00 USD with the twist grip/throttle included. Once I figured out that the choke mechanism works just the opposite of my round slide Mikunis (round slides you push the choke lever down to choke; flat slide is UP to choke!!) everything went pretty well. I don't remember the exact jetting that I used, but the bike seems to run pretty well. The idle is a bit higher that I'd like (about 1,500 rpm), but for me that's not a deal breaker. The bike seems to have good power, and good throttle response. Being as how the motor is fresh from a rebuild (1st over on the bore and a Wiseco 10.5 to 1 piston, a mild street cam, and a custom 2 into 1 exhaust) I haven't had the motor past 5000 rpm yet. As I said it pulls very strong to that point and there is no surging at steady speeds, ect. I've done a couple of plug checks and the plug is a dark brown color (might be a tad bit rich). So, yeah no more issues tuning it than to tuning my Mikuni round slides to the particular bike that they're on. As you know they're all a bit different in what they like for carburation.
Don't know if this helps you any, but that's my experience so far. Good luck! wiguzziman
I have an 82 FT that is a past road racer that I am bringing back to life to put back on the track this year and I have read many posts on the old site as well as googled my question and I am still a little unsure of the answer so I am here asking for wisdom.
I know the xl,xr flywheel is lighter and the starter has been removed from my FT so it has to be started on the rollers so can I replace the heavier flywheel with the ring gear with a lighter unit from the xl or xr? I do not run a battery as there is no lighting etc, on the bike. I am looking to make it rev a little quicker. It has a wiseco piston, mega cycle cam etc.
I tried to fit a XR/XL sidecover to the FT with the FT stator and Flywheel. This will not fit and it looks like at least the FT stator is thicker than the XL/XR stator. I do not know if that also means the flywheel of the FT is deeper.
If that is the case your XL/XR flywheel will not cover the whole FT stator. You do not need as much power as you used too because there is no big battery to charge but I don't know what the effect would be, could also be you have a less powerful spark.
Again this is only if the flywheel is less deep which I don't know. XR/XL flywheels are cheap so why not just buy one and compare? Installation is also very easy. Just put a rag between the gears and use a small screw-in puller in the flywheel.
Just found this link btw. Interesting to see there is a significant difference between the XL and XR flywheels.
I'm running an FCR-mx on mine. Doesn't answer your question about using a TM, but the FCR is gold.
Thanks for the response and link FT500, very informative. I was lucky to find an older racer that was into the Ascot for some time and he stated flat out that they will not work due to how the CDI is triggered etc. He said to pull the flywheel and put it in the lathe and turn the starter gear teeth off as there is drag created in the oil and this will help in gain RPM's quicker so I will do this.
Also has anyone gutted the inner pipes from the stock header? he said that was a good way to go with a super trapp on it but I would like to hear where it needs to be cut to get the inner pipes out. I would like to make as few cuts as possible.
This is what my son did on our family project. 3 cuts each side. lowest cut about 1.125" up from weld on on the collector. Other more or less in middle of the curves. Still haven't dealt with the welding scars, maybe a sandblast & re-coat with Jet Hot or ceramic. While it's all apart, you might also examine putting the collector up closer to the head & have only 1 downpipe ...
On another note, has anyone eliminated the gear drive for the tach in favour of something electronic? My first idea was to put only an old large Gold Wing tach with a tiny bicycle digital speedo.
Yup did that.
There is a part from a honda XL I think that blocks the hole in the valvecover. (valvecover needs to be removed to install it). I have it on both FT's
I have a cheap Aliexpress dash on the bratstyle FT and the rev counter is triggered by the trigger wire towards the coil. Speedo has a magnet glued to the front disk with a pickup.
For the race FT500 I have a spare Rev counter for a CBR600F1 that I hope to adapt to the FT. Rev range will be a bit off (FT max rev 8k and CBR max revs 14K) and I still have to check if the revs indicate correctly. The FT500 is a single cylinder while the CBR is a 4 cylinder but since the FT uses the waisted spark method and the CBR was triggered from 1 of 2 ignition coils I hope the amount of triggers per rev are the same and with that the Tacho will read the correct revs.
Wiring for those digital rev counters is usually very simple. A ground, a 12v source (usually switched 12v) and the trigger which you can tap from the trigger to the ignition coil.
Edit: This is the plug that neatly blocks the old tacho drive hole. It is a XL500R part.
Since I will be using my FT for racing I will have to take the side- and centerstand off. To make sure I can prop it up easily I welded some long nuts to the swingarm to which I can mount bobbins for a padockstand.
For suspension I went with Hagon shocks for the FT racer.
Chose the non-damping-adjustable ones because according to the importer who supported more racers, the progressive damping of the normal ones works better for road courses than the adjustable 2810 series where you set them on 1 damping which turns out to be sub-optimal a lot of the times.
The springs on the shocks are tailored to my weight, the bike and that I will be road racing it. I got 350mm length shocks (about 15mm longer than stock).
I also bought some progressive fork springs to complete the whole suspension setup. Like the stance a lot now.
I finally cut down the huge mudguard and made a muffler support bracket too
Good choice on the suspension bits. When I re-built my 83 street FT500 I decided to give the Hagon shocks a try as I'd seen them on a bunch of track bikes, and everyone that used them was very happy with them. I did however go with the 2810 series with the adjustable damping for the street. GREAT shocks!! I have them on my 83 street FT500, my 82 street legal Replica Road Racer FT500, and my 78 Yamaha SR500 street tracker. I eliminated the stock cable drive tach on the FT500's as well. I went to the hardware store and found a tapered rubber plug of the diameter that I needed and cut it to the proper length. It's a semi press fit in the old tach drive hole so it can't work it's way any further into the hole. Then I made a teardropped shaped flat cover out of some aluminum that I had laying around and mounted that over the rubber plug via the 6mm bolt hole that held the old tach drive in place. It's been over 2 years since I did this and no issues with leaks or anything else. wiguzziman
I have a right-hand grab handle for the FT if anyone is interested. Found it a couple of months ago and it took some head scratching before i remembered what it was.. My nephew just started powder coating, so he shot a coat of black on it for practice and it looks good. Hit me up if interested