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Discussion Starter #1
Hey guys. I’m currently installing the TB cam on my Grom since I have it sitting here in my garage. Im in the middle of the process and have two questions:

1.) Should I use the new tappet screws that came with the cam, or can I use the stock ones?

2.) Anyone know where I can find a replacement bolt for the cam tensioner (I think....its the bolt where the spring comes flying out). Mine is a bit rounded off because of my own stupidity, so I’m about to go searching for one.

Thanks guys!
 

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Definitely use the screws that come with the TB cam. They are longer. Due to the smaller base circle diameter of the TB cam, you will nearly run out of threads on the stock screws when setting the clearances.

As far as the bolt goes, I would say just order one from Partzilla, your local Honda dealer, or whoever you like to order parts from. Hopefully, you can make the one you have work, until you acquire a new one.

Anytime I round off a fastener while working on the Grom, I just replace it. Some of them are pretty soft. If the one you have is unusable, then maybe any appropriately sized metric bolt will be ok, until you can get the correct one. Not sure. I can’t remember, does the spring kind of fit over the end of the bolt? Is it a special bolt?

It’s been a while since I had mine out of the bike. Don’t forget to inject the tensioner with oil.
 

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Discussion Starter #3
Definitely use the screws that come with the TB cam. They are longer. Due to the smaller base circle diameter of the TB cam, you will nearly run out of threads on the stock screws when setting the clearances.

As far as the bolt goes, I would say just order one from Partzilla, your local Honda dealer, or whoever you like to order parts from. Hopefully, you can make the one you have work, until you acquire a new one.

Anytime I round off a fastener while working on the Grom, I just replace it. Some of them are pretty soft. If the one you have is unusable, then maybe any appropriately sized metric bolt will be ok, until you can get the correct one. Not sure. I can’t remember, does the spring kind of fit over the end of the bolt? Is it a special bolt?

It’s been a while since I had mine out of the bike. Don’t forget to inject the tensioner with oil.
Thank you! I contacted DHMotoring where I bought it from and TBParts themselves shortly after posting this, and they both said the stock tappets should work just fine. So maybe I will give it a try and see how much thread is left.

Yes, on the bolt it has a little nub type thing at the top where the spring sits on. Probably will have to purchase a new bolt, as the one I have is pretty rounded off. I was surprised at how tightly Honda put that bolt on from the factory, when I'm reading that the torque spec for it is only 16 ft lbs.
 

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I’ve seen people use the stock screws and it does work, but I’ve read where some people seemed a bit uneasy by how little thread was left. Let us know how your stock screws work out.

I had to remove the two M6x22 bolts that secure the rear master cylinder to the rearset the other day. They rounded off. It looks like there was red Loctite on them. Seems like overkill to me. It bent the Craftsman 8mm wrench. Lowe’s warrantied the wrench.
 

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I've seen people having issues with the TB screws, these are probably made out of Thaïtanium and get damaged to the point that where you need to make constant adjustments to the valve lash. Maybe these have been replaced by better ones, I don't know... And yes you'll have little thread left with the stock screws. One other way to make up for it would be lash caps, I think GF sells them. Definitely not a fan of the TB ''new but made like a regrind'' design, I think it's just stupid.
 

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I've seen people having issues with the TB screws, these are probably made out of Thaïtanium and get damaged to the point that where you need to make constant adjustments to the valve lash. Maybe these have been replaced by better ones, I don't know... And yes you'll have little thread left with the stock screws. One other way to make up for it would be lash caps, I think GF sells them. Definitely not a fan of the TB ''new but made like a regrind'' design, I think it's just stupid.
I thought the same thing. It is a brand new cam, so it would not have cost any additional money to manufacture it with a larger base circle diameter. It seems a bit lazy. I realize that the performance is good, but I believe the design could have been better executed. I’ve noticed most people don’t seem to care. It’s cheap and makes the bike go faster, therefore it is very popular.

I had not heard that about their screws. Good to know. I believe I saw a picture one time of a valve stem that was completely mushroomed. I wonder if the odd angle the screw makes contact with it, contributed to that?

A mushroomed valve stem would only exacerbate the situation regarding the reach of the screws.
 

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Discussion Starter #7
Thanks guys! I guess I will see how it goes. Only reason I went with TB over DCR was the price. Maybe I should have went DCR, but who knows. Hopefully all is well!
 

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I’m sure it will be ok. Glad to see you didn’t sell your bike.
 
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Discussion Starter #9
I’m sure it will be ok. Glad to see you didn’t sell your bike.
Thanks! Yeah, I decided to keep it and just install these upgrades I have. Hopefully I will be back on riding it again soon as I start feeling better!
 

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Discussion Starter #10
Quick question...what valve clearances (I think its called) should I use with my TB cam? I see some people mention .003 and .004 while others recommend stock settings.
 

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I run .003 intake and .004 exhaust on my DCR cam, I think TB is the same?
 

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A lot of people run them at .003IN/.003EX from what I read.

If it were me, I might go with .004EX like Ninelives17 is running. I would rather the valve be a little loose. You can always tighten it up more later if you need to.

I’m running .004IN and about .005EX. It is within Yoshimura’s specs, but there is a little bit of a ticking sound. I could tighten them up a bit more and still be within their spec range.
 

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Discussion Starter #14
A lot of people run them at .003IN/.003EX from what I read.

If it were me, I might go with .004EX like Ninelives17 is running. I would rather the valve be a little loose. You can always tighten it up more later if you need to.

I’m running .004IN and about .005EX. It is within Yoshimura’s specs, but there is a little bit of a ticking sound. I could tighten them up a bit more and still be within their spec range.
Good to know, thank you! I’ll go with the .003IN and .004EX specs like Ninelives17 said. All I am waiting on now is the new bolt I ordered from the local dealer, and my ECU to get here from CJR (I think they are currently out of the shop doing some moto racing).
 

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Discussion Starter #15
I got the ECU in and installed the cam along with intake! I decided to take it for a little ride just to see what its like. I only rode it for a few minutes, but it seems to pull harder at the upper RPM range for sure. I did notice that there was white smoke coming out from where the exhaust mates with the engine. So I started it again, and noticed it would show up when giving the bike revs after the exhaust was heated up. What could that be? Is it just residual oil that I may have missed when cleaning up burning off, or is it a bigger concern?
 

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Probably oil, clean exhaust and under engine real good and try again.
 

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I always clean my exhaust real good after working on my bike with rubbing alcohol. I put some on a paper towel and also use a Q-Tip for any small, tight spots. Just the stainless parts. Removes any oil and fingerprints. That way they don’t get cooked on once the bike is up to temperature.
 
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Discussion Starter #20
I always clean my exhaust real good after working on my bike with rubbing alcohol. I put some on a paper towel and also use a Q-Tip for any small, tight spots. Just the stainless parts. Removes any oil and fingerprints. That way they don’t get cooked on once the bike is up to temperature.
Thats a good idea! I'll have to get some rubbing alcohol to keep on hand. I've just been using brakleen on a shop rag to wipe down the exhaust. Probably pretty crude, but its worked to keep the fingerprints off.
 
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