The Hodaka Club Forum

Hi All! Long time lurker, first time caller so to speak. First off, I love old enduros. I’ve always loved dirtbikes but don’t ride in the dirt much anymore. But with old street legal enduros, I can still have fun in the dirt a bit, on the road a bit, and still afford to raise three kids! I’ve always admired the simplicity and functionality of the Hodakas and I’m a sucker for that shiny toaster tank too! I finally have one! A 1970 Ace 100 that’s a runner with some wear but mostly all there. And she’s a runner! I can’t believe how it starts and purrs on one or two kicks l! But it needs some love. I’m working on it with your help!
I’m hoping someone can help me with the carb needle settings and maybe link or two to other threads. My internet connection is sketchy and slow so I’m hoping for some guidance. It starts and runs well through first and second gear. It starts to bog out above third gear. It may be compression but the way it runs to that point I hope it’s a simpler fix. Thanks in advance for any help!

Johnny, welcome to the group. Nice little bike you have and see one nice upgrade right off the bat, 1 down 4 up shift cover. Can I suggest letting us know where about you live, good chance another Hodaka Club member may be close. Also if you join the Hodaka Club at Hodakaclub.org for $24 per year, you will have access to many back issues of the club newsletter with tons of tips. Im sure a carb expert will be chiming in soon. You also have a very nice work space.
Kelly

I dig the Enduros too.

Looks like you maybe have an Ace 100 B there. I notice she doesn’t have the Ace fuel tank. It’s either a Wombat or Dirt Squirt tank. The Ace’s all had a red gas cap with a smaller opening. But no worries!

You may need to pull the carb off of her and clean it really well. You could have dirty jets, or maybe your needle isn’t set to the proper height. But if it sat for a good while it’s a good bet the carb needs a good cleaning.
Get yourself a couple of cans of carb cleaner. Also get yourself a copy of the Ace 90/100/100B/Super Rat shop manual. You can usually find them on eBay for around $30-40. Get the last one which includes the B model and the Super Rat to be sure you have all the updates for your model bike.

Also, if you post the frame serial number (on the VIN plate) and the engine serial number, on the right casing below the clutch lever on the case, we can help you determine for sure which model Ace she is!

Mine is a 1971 Ace 100 B+ and I have both a Wombat tank and an Ace tank for her. Here’s a photo with the Wombat tank!

Welcome to the Forum! Victor

Before working on jetting, lets be sure the air cleaner still cleans air and still passes air easily. Lets also be sure the exhaust system - especially the silencer/spark arrestor parts - aren't severely carboned up. And as suggested, lets fully clean the carb internals . . . all jets and ALL passages in the carb too. Then check how it runs. OK?
Ed
PS: Welcome to the group! Y'all are gonna have some fun!

Captain Eddie is right about the air filter & the exhaust. Make sure the air filter is clean & properly lubricated. It needs a bit of oil to filter well. But dirt will cut air flow.

Then, pull of the exhaust pipe and start a fire! Place the pipe on the hot fire and let it bake for a while. I’ve done this to 3 or 4 pipes so far. If the pipe is carboned up and full of old 2 stroke oil byproducts, burning it clean this way can really improve the flow through the pipe. Just don’t do the BBQ if you have a chrome exhaust. But the black pipes can be BBQ’d and then repainted with high heat engine paint! Victor

Captain Eddie is right about the air filter & the exhaust. Make sure the air filter is clean & properly lubricated. It needs a bit of oil to filter well. But dirt will cut air flow.

Then, pull of the exhaust pipe and start a fire! Place the pipe on the hot fire and let it bake for a while. I’ve done this to 3 or 4 pipes so far. If the pipe is carboned up and full of old 2 stroke oil byproducts, burning it clean this way can really improve the flow through the pipe. Just don’t do the BBQ if you have a chrome exhaust. But the black pipes can be BBQ’d and then repainted with high heat engine paint! Victor

Hey Kelly! In the photo of your bike in the line with other bikes, I see my first bike (same model/year) right next to yours! It’s a Kawasaki F6 125cc enduro. Rotary valve carb! I wish I still had that bike today! Victor

Hey fellas! Chiming in here. After taking off my spark arrestor and baffle and seeing a few dead spiders that might be older than my father, I am giving my exhaust a thorough cleaning today. I’m having difficulty getting my exhaust nut off. It doesn’t seem to be too caked up with rust, just very stubborn. I’m honestly not sure of which way to turn it-clockwise or counter. Picture for clarity.

Standard thread (lefty, loosey - righty, tighty). A bit of heat from a propane torch will likely help - especially if you heat the gland nut pretty aggressively so you get it hot before the cylinder threads come up to temp . . . should loosen more easily then.

Ed

One other thing to try. The rear sprocket looks very small. You might try a little bit bigger one to give the bike a little more snap (it just won't have the same top speed - but then again it doesn't sound like it is making it to top speed anyways.)

Thanks for the replies guys! I’m also spending much of my free time(and funds!) on the new work space/building so I haven’t been able to do too much yet. Hoping to get power and some heat and insulation in this fall/winter so I can enjoy it in our cold Mid Ohio winters. Socalhodaka, I envy ur geography for riding every time I read the cycle mags and see great pics like yours! Yes I’m pretty close to the mid Ohio vintage days event so that helps too. Hoping to get there this year for only the second time. Loved the swap meet the first time!
-Air filter looks pretty good for now but want to repack and oil it.
- Good points on the exhaust and gearing. I thought the sprocket looked awfully small but believe it was stock for 72 from vintage articles. May be adding a few teeth eventually.
- still need to clean the carb! Feels like the main or settings may help as it fires on first kick and runs great until about 4th gear. But could be all of above mentioned too. I’ll get there eventually!
Here’s a few more pics of the tags to help with ID. Thanks for the tank info btw!

Had to add a pic of the bike that started it all! 1972 Suzuki Prospector 125. Back in 1987 When I was 12 I finally got a real dirtbike after riding a Yamaha RD250 streetbike a year in the dirt with street tires, I got on one of those dual range lightweight(comparatively!) machines and fell in love. This one is a much better example than my original that I rolled into the landfill with my Dad a year later after I huffed it(doh stupid me!). Me and my Honda SL100 riding buddy were riding the Rover Gas Pipeline cut through miles of corn and soybean fields. A good day.

Don't beat yourself up too bad over dropping Suzie off at the landfill. We probably all have one of "those" stories. For me, '72 Super Rat into the scrap metal tub at the service station where I worked. Ugh. Cool bikes by the way.

I'm kind of stumped by the statement that it runs great until about 4th gear. Are you familiar with small bore oomph (or comparative lack there-of)? 100cc two strokes - it's OK to rev 'em. They are pretty happy when they are spinnin' - not so much when they are grunting.
Ed

Hi Ed,
It winds up good through 3rd gear but cannot maintain power through 4th. If I downshift into 3rd it will stay in the revs (most of the time). Can’t even get to 5th. It could just be low on compression. This is all on the road btw. Need to do a full carb clean first.

A couple of things, check that the timing is spot on. Do a compression test. Then go thru the carb and clean it. If it flattens out in 4th, I'd say a timing issue or fuel flow.

When was the last time you cleaned your pipe ? It sounds like a clogged exhaust to me.

Larry S

I would take a quick compression test using a simple tester in the spark plug hole before I went any further. If it is slowing down under increasing loads, it can be the fact that the original 6 or 7 horsepower it had when fresh is now considerable lower. It takes a lot of power to keep a 40 year old motorcycle accelerating in 4 or 5th gear. I have found one or both of the rings stuck in the piston as a result of sitting or from carbon build up. Freeing them up was all it took.

A pipe full of old unburned oil residue will definitely slow things down. I have loosened the pipe nut to allow some of the exhaust to escape as a quick check to confirm exhaust issues.

Cool tip, Dogs. It never occurred to me to make that move so as to eliminate exhaust restriction as the culprit when working up a power issue. Cool.

Thanks for the info guys! I’m going to try the exhaust tip tomorrow olddogs. My gut tells me compression but I don’t have a compression tester yet. It’s on my list of wants. I hope it isn’t. And am thinking carburation isn’t a problem as this old girl fires right up with one or two kicks after sitting a week and runs well up to 4th but u never know. I’ve owned my share of bikes and have never had one that fires and purrs as quickly as this one. They nailed that part! It still amazes me.

Just checking back in finally. Darn life!

I’ve got good compression and am pretty sure it’s just that I’m a fattish oldish man trying to expect too much out of the 36 tooth sprocket that’s on it. On a whim I ordered a 52 tooth 420 chain sprocket from Terry at Hodaka parts. I may have not done enough homework. I never even knew these random offshoot 428/4?? Chains existed! Will 420 work on my Ace 100? And if it does can I reach 40+ mph road putting with that many extra teeth? Thanks for the input. I’m fine with the way it is if it doesn’t work out. I still enjoy it as is!

Go build a small fire and BBQ the pipe. Take all the tail pieces out and let it heat up in the fire & burn away the carbon & oil built up in the pipe. Just for fun, weigh the pipe before & after.

My Ace pipe had so much in it that it flamed like a torch out both ends until it burned clean! Victor